Lee Cecil Fletcher Sallows (born April 30, 1944) is a British electronics engineer known for his contributions to recreational mathematics. He is particularly noted as the inventor of golygons, self-enumerating sentences, and geomagic squares. Sallows has an Erdős number of 2.[1][2]
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Sallows is an expert on the theory of magic squares[3] and has invented several variations on them, including alphamagic squares[4][5] and geomagic squares.[6] The latter invention caught the attention of mathematician Peter Cameron who has said that he believes that "an even deeper structure may lie hidden beyond geomagic squares"[7]
In 1984 Lee Sallows invented the self-enumerating sentence—a sentence that inventories it own letters. Following failure in his attempt to write a computer program to generate such sentences, he constructed a so-called electronic Pangram Machine, among the results of which was the following sentence that appeared in Douglas Hofstadter's Metamagical Themas column in Scientific American in October 1984:[8]
This Pangram contains four as, one b, two cs, one d, thirty es, six fs, five gs, seven hs, eleven is, one j, one k, two ls, two ms, eighteen ns, fifteen os, two ps, one q, five rs, twenty-seven ss, eighteen ts, two us, seven vs, eight ws, two xs, three ys, & one z.
A golygon is a polygon containing only right angles, such that adjacent sides exhibit consecutive integer lengths. Golygons were invented and named by Sallows[2] and introduced by A.K. Dewdney in the Computer Recreations column of the July 1990 issue of Scientific American.[9]
Lee Cecil Fletcher Sallows was born at Welwyn, Hertfordshire in England and until the age of 26 lived in London. Since 1970 he has lived in Nijmegen in the Netherlands where until recently he was an electronics engineer at Radboud University. In 1973 Sallows met up with his Dutch partner Evert Lamfers, with whom he has lived ever since.