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Composite numbers which in base 6 contain their largest proper factor as a substring.
1

%I #3 Mar 30 2012 17:30:32

%S 9,403,8383,9287,14299,15403,16459,17543,19291,20989,25807,26743,

%T 30301,68191,96307,111277,120059,121903,158299,166391,195583,221443,

%U 238603,248551,292499,317131,356879,403927,421901,422419,440599,443119,457297

%N Composite numbers which in base 6 contain their largest proper factor as a substring.

%t Do[ If[ !PrimeQ[ n ] && StringPosition[ ToString[ FromDigits[ IntegerDigits[ n, 6 ] ] ], ToString[ FromDigits[ IntegerDigits[ Divisors[ n ] [ [ -2 ] ], 6 ] ] ] ] != {}, Print[ n ] ], {n, 2, 10^6} ]

%Y Cf. A062238.

%K base,nonn

%O 1,1

%A _Robert G. Wilson v_, Aug 08 2001