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A063156
Composite numbers which in base 6 contain their largest proper factor as a substring.
1
9, 403, 8383, 9287, 14299, 15403, 16459, 17543, 19291, 20989, 25807, 26743, 30301, 68191, 96307, 111277, 120059, 121903, 158299, 166391, 195583, 221443, 238603, 248551, 292499, 317131, 356879, 403927, 421901, 422419, 440599, 443119, 457297
OFFSET
1,1
MATHEMATICA
Do[ If[ !PrimeQ[ n ] && StringPosition[ ToString[ FromDigits[ IntegerDigits[ n, 6 ] ] ], ToString[ FromDigits[ IntegerDigits[ Divisors[ n ] [ [ -2 ] ], 6 ] ] ] ] != {}, Print[ n ] ], {n, 2, 10^6} ]
CROSSREFS
Cf. A062238.
Sequence in context: A266924 A157599 A063876 * A058850 A151632 A035024
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Aug 08 2001
STATUS
approved