2 Feb
2012
2 Feb
'12
11:57 p.m.
David Wilson and Warren Smith batted about the side puzzle: When can the reciprocal of a composite N contain every digit combination of length floor[log10(N)]? Smith (roughly) argued 'never', and Wilson pointed out that some prime powers worked. Adding a bit more fuel: The reciprocals of 343 (7^3), 841 (29^2), and 799 (17*47) each contain all two-digit combinations. Rich