| Numeral systems by culture | |
|---|---|
| Hindu-Arabic numerals | |
| Western Arabic (Hindu numerals) Eastern Arabic Indian family Tamil |
Burmese Khmer Lao Mongolian Thai |
| East Asian numerals | |
| Chinese Japanese Suzhou |
Korean Vietnamese Counting rods |
| Alphabetic numerals | |
| Abjad Armenian Āryabhaṭa Cyrillic |
Ge'ez Greek Georgian Hebrew |
| Other systems | |
| Aegean Attic Babylonian Brahmi Egyptian Etruscan Inuit |
Kharosthi Mayan Quipu Roman Sumerian Urnfield |
| List of numeral system topics | |
| Positional systems by base | |
| Decimal (10) | |
| 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 20, 24, 30, 36, 60, 64 | |
| Non-positional system | |
| Unary numeral system (Base 1) | |
| List of numeral systems | |
Base 30 or trigesimal is a positional numeral system using 30 as the radix. Digits in this base can be represented using the Arabic numerals 0-9 and the Latin letters A-T.
From a mathematical viewpoint, 30 is a convenient choice for a base in that it is the 4th primorial number; many vulgar fractions are easily expressed in base 30. On the other hand, base 30 has poor radix economy, and it shares the problem with base 60 of its radix falling between twin primes, resulting in few recurring fractions having short periods.
| Decimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Base 30 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E |
| Decimal | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 |
| Base 30 | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T |
| Decimal base Prime factors of the base: 2, 5 |
Base 30 Prime factors of the base: 2, 3, 5 |
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| Fraction | Prime factors of the denominator |
Positional representation | Positional representation | Prime factors of the denominator |
Fraction |
| 1/2 | 2 | 0.5 | 0.F | 2 | 1/2 |
| 1/3 | 3 | 0.3333... = 0.3 | 0.A | 3 | 1/3 |
| 1/4 | 2 | 0.25 | 0.7F | 2 | 1/4 |
| 1/5 | 5 | 0.2 | 0.6 | 5 | 1/5 |
| 1/6 | 2, 3 | 0.16 | 0.5 | 2, 3 | 1/6 |
| 1/7 | 7 | 0.142857 | 0.48H | 7 | 1/7 |
| 1/8 | 2 | 0.125 | 0.3MF | 2 | 1/8 |
| 1/9 | 3 | 0.1 | 0.3A | 3 | 1/9 |
| 1/10 | 2, 5 | 0.1 | 0.3 | 2, 5 | 1/A |
| 1/11 | 11 | 0.09 | 0.2LOGAR85DJ | B | 1/B |
| 1/12 | 2, 3 | 0.083 | 0.2F | 2, 3 | 1/C |
| 1/13 | 13 | 0.076923 | 0.296RKN | D | 1/D |
| 1/14 | 2, 7 | 0.0714285 | 0.248H | 2, 7 | 1/E |
| 1/15 | 3, 5 | 0.06 | 0.2 | 3, 5 | 1/F |
| 1/16 | 2 | 0.0625 | 0.1Q7F | 2 | 1/G |
| 1/17 | 17 | 0.0588235294117647 | 0.1MS7 | H | 1/H |
| 1/18 | 2, 3 | 0.05 | 0.1K | 2, 3 | 1/I |
| 1/19 | 19 | 0.052631578947368421 | 0.1HB | J | 1/J |
| 1/20 | 2, 5 | 0.05 | 0.1F | 2, 5 | 1/K |
| 1/21 | 3, 7 | 0.047619 | 0.1CPL | 3, 7 | 1/L |
| 1/22 | 2, 11 | 0.045 | 0.1AR85DJ2LOG | 2, B | 1/M |
| 1/23 | 23 | 0.0434782608695652173913 | 0.193RBM56FJGSKQ2I7ONEAD | N | 1/N |
| 1/24 | 2, 3 | 0.0416 | 0.17F | 2, 3 | 1/O |
| 1/25 | 5 | 0.04 | 0.16 | 5 | 1/P |
| 1/26 | 2, 13 | 0.0384615 | 0.14IDPBG | 2, D | 1/Q |
| 1/27 | 3 | 0.037 | 0.13A | 3 | 1/R |
| 1/28 | 2, 7 | 0.03571428 | 0.1248H | 2, 7 | 1/S |
| 1/29 | 29 | 0.0344827586206896551724137931 | 0.1 | T | 1/T |
| 1/30 | 2, 3, 5 | 0.03 | 0.1 | 2, 3, 5 | 1/10 |