This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A225649 #10 May 22 2013 16:59:27 %S A225649 2,3,4,6,10,12,14,15,16,18,20,21,22,24,25,26,28,30,32,33,34,35,36,38, %T A225649 39,40,42,44,45,46,48,49,50,51,52,54,55,56,57,58,60,62,63,64,65,66,68, %U A225649 69,70,72,74,75,76,77,78,80,81,82,84,85,86,87,88,90,91,92 %N A225649 Positions of non-ones in A225650, numbers n such that n and A000793(n) have at least one common divisor > 1. %C A225649 Which composites are missing apart from 8, 9 and 27? See comment at A225648. %o A225649 (Scheme with _Antti Karttunen_'s IntSeq-library): %o A225649 (define A225649 (MATCHING-POS 1 1 (lambda (i) (> (gcd (A000793 i) i) 1)))) %Y A225649 Cf. A225648 (complement), A225651 (from n>1 onward is a subset). %Y A225649 Cf. A225650, A225640. %K A225649 nonn %O A225649 1,1 %A A225649 _Antti Karttunen_, May 13 2013