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%I #5 Jun 24 2014 01:10:00
%S 4,9,407,25,9,49,893,1387,15,121,23533,169,21,4717,10579,289,27,361,
%T 25,49,33,529,32437,61903,39,24523,35,841,45,961,39917,77,51,64993,
%U 111277,1369,57,91,99101,1681,49,1849,55,108389,69,2209,207133,139163
%N Smallest composite number in base n which contains its largest proper factor as a substring.
%t sublist[ s_, l_ ] := Module[ {i, ls=Length[ s ]}, For[ i=1, i+ls-1<=Length[ l ], i++, If[ s==Take[ l, {i, i+ls-1} ], Return[ True ] ] ]; False ]; a[ n_ ] := Module[ {k}, For[ k=4, True, k++, If[ !PrimeQ[ k ]&&sublist[ IntegerDigits[ Divisors[ k ][ [ -2 ] ], n ], IntegerDigits[ k, n ] ], Return[ k ] ] ] ];
%Y Cf. A062238.
%K base,nonn
%O 2,1
%A _Robert G. Wilson v_, Aug 08 2001
%E More terms from _Dean Hickerson_, Aug 10, 2001