# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a063889 Showing 1-1 of 1 %I A063889 #4 Mar 30 2012 17:30:33 %S A063889 4087,5083,5731,8857,10841,11983,15109,18631,27317,29593,49883,52319, %T A063889 61903,62317,65509,67237,80371,87707,89351,101971,108781,114313, %U A063889 121801,129739,136921,140033,143231,147923,158497,167477,186911,199841,202537 %N A063889 Composite numbers not divisible by 5 which in base 5 contain their largest proper factor as a substring. %t A063889 Do[ If[ !PrimeQ[ n ] && Mod[ n, 5 ] != 0 && StringPosition[ ToString[ FromDigits[ IntegerDigits[ n, 5 ] ] ], ToString[ FromDigits[ IntegerDigits[ Divisors[ n ][ [ -2 ] ], 5 ] ] ] ] != {}, Print[ n ] ], {n, 3, 10^6} ] %K A063889 nonn %O A063889 1,1 %A A063889 _Robert G. Wilson v_, Aug 27 2001 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE