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 A133382 #3 Mar 31 2012 13:48:24 %S A133382 75,525,3940 %N A133382 Numbers n such that gcd( n!-1, 2^n-1 ) is neither 1 nor 2n+1. %C A133382 This subsequence of A068483 lists the rare exceptions for which gcd( N!, 2^N-1 ) <> 2N+1. Is it finite? Are all elements multiples of 5? %o A133382 (PARI) for(n=1,10^5,if((g=gcd(n!-1,2^n-1)-1) & g!=2*n,print(n", "))) %Y A133382 Cf. A068483, A068480. %K A133382 nonn,bref %O A133382 1,1 %A A133382 _M. F. Hasler_, Oct 28 2007