KenKen

From Wikipedia, the free encyclopedia

KenKen (tm) is a mathematical and logical puzzle loosely similar to sudoku. It was invented by a Japanese mathematics teacher Tetsuya Miyamoto, innovator of the theory "The Art Of Teaching Without Teaching", as an 'instruction-free' method of training the brain and was later published in The Times in March 2008. It was introduced to The Times via Robert Fuhrer of Nextoy and Chess Champion Dr. David Levy and recognized for its depth and magnitude by The Times features editor, Mr. Michael Harvey. KenKen(tm) brain training puzzles are a trademark of Nextoy, LLC. Renowned toy inventor, Robert Fuhrer, founder of Nextoy discovered KenKen (aka KEN-KEN) in Japan as the original books published by educational publisher Gakken Co., Ltd. as Kashikoku naru Puzzle, and has been instrumental in introducing them to the western world.

A typical KenKen problem. This diagram uses / in place of ÷.
A typical KenKen problem. This diagram uses / in place of ÷.

The objective is to fill the grid in with the digits 1 through 6 such that:

  • Each row contains exactly one of each digit
  • Each column contains exactly one of each digit
  • Each bold-outlined group of cells contains digits which achieve the specified result using the specified mathematical operation: addition (+), subtraction (-), multiplication (x), and division (/). Unlike Killer sudoku, digits may repeat within a group.

Some of the techniques from sudoku and killer sudoku can be used here, but much of the process involves the listing of all the possible options and eliminating the options one by one as other information requires. One major distinction of KenKen from sudoku is that there are multiple ways to an answer. One can finish a puzzle and then erase the answers to try to solve it in a more efficient way.

In the example here:

  • "11+" in the leftmost column can only be "5,6"
  • "2/" in the top row must be one of "1,2", "2,4" or "3,6"
  • "20x" in the top row must be "4,5".
  • "6x" in the top right must be "1,1,2,3". Therefore the two "1"s must be in separate columns, thus row 1 column 5 is a "1".
  • "240x" on the left side is one of "6,5,4,2" or "3,5,4,4". Either way there is a five and it must be in the right pair of cells since we have "5,6" already in column 1.
  • etc
Solution to the above problem. This diagram uses / in place of ÷.
Solution to the above problem. This diagram uses / in place of ÷.

More complex KenKen problems are formed using the principles described above but omitting the +-x/ symbol leaving them as yet another unknown to be determined.


[edit] Data Tables

The following table evaluate the various combinations of 2, 3, 4 and 5 cells for each operation. For instance, 4 may be obtained by multiplying the four digits 1, 1, 2 and 2 together.

Where a group of digits includes repeats, then it must be part of a kinked group not a linear one.

                              1    -12                          =                 2    *112
                              1    -23                          =                 3    *113
                              1    -34                          =  4    +112      4    *114
                              1    -45                          =                 4    *122
                              1    -56                          =  5    +113      5    *115
               2    *12       2    -13       2    /12           =  5    +122
                              2    -24       2    /24           =  6    +114      6    *116
                              2    -35       2    /36           =  6    +123      6    *123
                              2    -46                          =  7    +115
3    +12       3    *13       3    -14       3    /13           =  7    +124
                              3    -25       3    /26           =  7    +133
                              3    -36                          =  7    +223
4    +13       4    *14       4    -15       4    /14           =  8    +116      8    *124
                              4    -26                          =  8    +125
5    +14       5    *15       5    -16       5    /15           =  8    +134
5    +23                                                        =  8    +224
6    +15       6    *16                      6    /16           =  8    +233
6    +24       6    *23                                         =  9    +126      9    *133
7    +16                                                        =  9    +135
7    +25                                                        =  9    +144
7    +34                                                        =  9    +225
8    +26       8    *24                                         =  9    +234
8    +35                                                        =  10   +136      10   *125
9    +36                                                        =  10   +145
9    +45                                                        =  10   +226
10   +46       10   *25                                         =  10   +235
11   +56                                                        =  10   +244
               12   *26                                         =  10   +334
               12   *34                                         =  11   +146
               15   *35                                         =  11   +155
               18   *36                                         =  11   +236
               20   *45                                         =  11   +245
               24   *46                                         =  11   +335
               30   *56                                         =  11   +344
=================================================================  12   +156      12   *126
8    +11222    8    *11222                                      =  12   +246      12   *134
9    +11223                                                     =  12   +255      12   *223
10   +11224                                                     =  12   +336
10   +11233                                                     =  12   +345
11   +11225                                                     =  13   +166
11   +11234                                                     =  13   +256
11   +11333                                                     =  13   +346
12   +11226    12   *11223                                      =  13   +355
12   +11235                                                     =  13   +445
12   +11244                                                     =  14   +266
12   +11334                                                     =  14   +356
12   +12333                                                     =  14   +446
13   +11236                                                     =  14   +455
13   +11245                                                     =  15   +366      15   *135
13   +11335                                                     =  15   +456      16   *144
13   +11344                                                     =  16   +466      16   *224
13   +12334                                                     =  16   +556
13   +22333                                                     =  17   +566
14   +11246                                                     =                 18   *136
14   +11255                                                     =                 18   *233
14   +11336                                                     =                 20   *145
14   +11345                                                     =                 20   *225
14   +11444                                                     =                 24   *146
14   +12335                                                     =                 24   *226
14   +12344                                                     =                 24   *234
14   +22334                                                     =                 25   *155
15   +11256                                                     =                 30   *156
15   +11346                                                     =                 30   *235
15   +11355                                                     =                 32   *244
15   +11445                                                     =                 36   *166
15   +12336                                                     =                 36   *236
15   +12345                                                     =                 36   *334
15   +12444                                                     =                 40   *245
15   +22335                                                     =                 45   *335
15   +22344                                                     =                 48   *246
16   +11266    16   *11224                                      =                 48   *344
16   +11356                                                     =                 50   *255
16   +11446                                                     =                 54   *336
16   +11455                                                     =                 60   *256
16   +12346                                                     =                 60   *345
16   +12355                                                     =                 72   *266
16   +12445                                                     =                 72   *346
16   +13444                                                     =                 75   *355
16   +22336                                                     =                 80   *445
16   +22345                                                     =                 90   *356
16   +22444                                                     =                 96   *446
17   +11366                                                     =                 100  *455
17   +11456                                                     =                 108  *366
17   +11555                                                     =                 120  *456
17   +12356                                                     =                 144  *466
17   +12446                                                     =                 150  *556
17   +12455                                                     =                 180  *566
17   +13445                                                     ============================
17   +22346                                                     =                 4    *1122
17   +22355                                                     =  6    +1122     6    *1123
17   +22445                                                     =  7    +1123
17   +23444                                                     =  8    +1124     8    *1124
18   +11466    18   *11233                                      =  8    +1133
                                                                =  8    +1223
18   +11556                                                     =  9    +1125     9    *1133
18   +12366                                                     =  9    +1134
18   +12456                                                     =  9    +1233
18   +12555                                                     =  10   +1126     10   *1125
18   +13446                                                     =  10   +1135
18   +13455                                                     =  10   +1144
18   +22356                                                     =  10   +1234
18   +22446                                                     =  10   +2233
18   +22455                                                     =  11   +1136
18   +23445                                                     =  11   +1145
18   +33444                                                     =  11   +1235
19   +11566                                                     =  11   +1244
19   +12466                                                     =  11   +2234
19   +12556                                                     =  12   +1146     12   *1126
19   +13456                                                     =  12   +1155     12   *1134
19   +13555                                                     =  12   +1236
19   +22366                                                     =  12   +1245
19   +22456                                                     =  12   +1344
19   +22555                                                     =  12   +2235
19   +23446                                                     =  12   +2244
19   +23455                                                     =  13   +1156
19   +33445                                                     =  13   +1246
20   +11666    20   *11225                                      =  13   +1255
20   +12566                                                     =  13   +1345
20   +13466                                                     =  13   +2236
20   +13556                                                     =  13   +2245
20   +14555                                                     =  13   +2344
20   +22466                                                     =  14   +1166
20   +22556                                                     =  14   +1256
20   +23456                                                     =  14   +1346
20   +23555                                                     =  14   +1355
20   +33446                                                     =  14   +2246
20   +33455                                                     =  14   +2255
21   +12666                                                     =  14   +2345
21   +13566                                                     =  14   +3344
21   +14556                                                     =  15   +1266     15   *1135
21   +22566                                                     =  15   +1356
21   +23466                                                     =  15   +1455
21   +23556                                                     =  15   +2256
21   +24555                                                     =  15   +2346
21   +33456                                                     =  15   +2355
21   +33555                                                     =  15   +3345
22   +13666                                                     =  16   +1366     16   *1144
22   +14566                                                     =  16   +1456
22   +22666                                                     =  16   +2266
22   +23566                                                     =  16   +2356
22   +24556                                                     =  16   +2455
22   +33466                                                     =  16   +3346
22   +33556                                                     =  16   +3355
22   +34555                                                     =  17   +1466
23   +14666                                                     =  17   +2366
23   +23666                                                     =  17   +2456
23   +24566                                                     =  17   +3356
23   +33566                                                     =  17   +3455
23   +34556                                                     =  18   +1566     18   *1136
23   +44555                                                     =  18   +2466     18   *1233
24   +15666    24   *11226                                      =  18   +3366
24   +24666    24   *11234                                      =  18   +3456
24   +33666                                                     =  18   +4455
24   +34566                                                     =  19   +2566
24   +44556                                                     =  19   +3466
25   +25666                                                     =  19   +4456
25   +34666                                                     =  20   +3566     20   *1145
25   +44566                                                     =  20   +4466
26   +35666                                                     =  21   +4566
26   +44666                                                     =  22   +5566
27   +45666    27   *11333                                      =                 24   *1146
28   +55666                                                     =                 24   *1234
               30   *11235                                      =                 25   *1155
               32   *11244                                      =                 30   *1156
               36   *11236                                      =                 30   *1235
               36   *11334                                      =                 32   *1244
               40   *11245                                      =                 36   *1166
               45   *11335                                      =                 36   *1236
               48   *11246                                      =                 36   *2233
               48   *11344                                      =                 40   *1245
               50   *11255                                      =                 48   *1246
               54   *11336                                      =                 48   *1344
               54   *12333                                      =                 48   *2234
               60   *11256                                      =                 50   *1255
               60   *11345                                      =                 60   *1256
               64   *11444                                      =                 60   *1345
               72   *11266                                      =                 60   *2235
               72   *11346                                      =                 64   *2244
               72   *12334                                      =                 72   *1266
               75   *11355                                      =                 72   *1346
               80   *11445                                      =                 72   *2236
               90   *11356                                      =                 75   *1355
               90   *12335                                      =                 80   *2245
               96   *11446                                      =                 90   *1356
               96   *12344                                      =                 96   *2246
               100  *11455                                      =                 96   *2344
               108  *11366                                      =                 100  *1455
               108  *12336                                      =                 100  *2255
               108  *22333                                      =                 108  *1366
               120  *11456                                      =                 120  *1456
               120  *12345                                      =                 120  *2256
               125  *11555                                      =                 120  *2345
               128  *12444                                      =                 144  *1466
               144  *11466                                      =                 144  *2266
               144  *12346                                      =                 144  *2346
               144  *22334                                      =                 144  *3344
               150  *11556                                      =                 150  *2355
               150  *12355                                      =                 180  *1566
               160  *12445                                      =                 180  *2356
               180  *11566                                      =                 180  *3345
               180  *12356                                      =                 200  *2455
               180  *22335                                      =                 216  *2366
               192  *12446                                      =                 216  *3346
               192  *13444                                      =                 225  *3355
               192  *22344                                      =                 240  *2456
               200  *12455                                      =                 270  *3356
               216  *11666                                      =                 288  *2466
               216  *12366                                      =                 300  *3455
               216  *22336                                      =                 324  *3366
               240  *12456                                      =                 360  *2566
               240  *13445                                      =                 360  *3456
               240  *22345                                      =                 400  *4455
               250  *12555                                      =                 432  *3466
               256  *22444                                      =                 480  *4456
               288  *12466                                      =                 540  *3566
               288  *13446                                      =                 576  *4466
               288  *22346                                      =                 720  *4566
               300  *12556                                      =                 900  *5566
               300  *13455
               300  *22355
               320  *22445
               360  *12566
               360  *13456
               360  *22356
               375  *13555
               384  *22446
               384  *23444
               400  *22455
               432  *12666
               432  *13466
               432  *22366
               450  *13556
               480  *22456
               480  *23445
               500  *14555
               500  *22555
               540  *13566
               576  *22466
               576  *23446
               576  *33444
               600  *14556
               600  *22556
               600  *23455
               648  *13666
               720  *14566
               720  *22566
               720  *23456
               720  *33445
               750  *23555
               864  *14666
               864  *22666
               864  *23466
               864  *33446
               900  *23556
               900  *33455
               1000 *24555
               1080 *15666
               1080 *23566
               1080 *33456
               1125 *33555
               1200 *24556
               1296 *23666
               1296 *33466
               1350 *33556
               1440 *24566
               1500 *34555
               1620 *33566
               1728 *24666
               1800 *34556
               1944 *33666
               2000 *44555
               2160 *25666
               2160 *34566
               2400 *44556
               2592 *34666
               2880 *44566
               3240 *35666
               3456 *44666
               4320 *45666
               5400 *55666

[edit] References