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 A091227 #7 Mar 31 2012 14:02:20 %S A091227 0,1,2,0,0,0,3,0,0,0,4,0,5,0,0,0,0,0,6,0,0,0,0,0,7,0,0,0,0,0,8,0,0,0, %T A091227 0,0,9,0,0,0,10,0,0,0,0,0,11,0,0,0,0,0,0,0,12,0,0,0,13,0,14,0,0,0,0,0, %U A091227 15,0,0,0,0,0,16,0,0,0,0,0,0,0,0,0,0,0,0,0,17,0,0,0,18,0,0,0,0,0,19,0 %N A091227 Inverse function of A014580: position in A014580 if the n-th GF(2)[X] polynomial is irreducible, 0 otherwise. %H A091227 A. Karttunen, <a href="/A091247/a091247.scm.txt">Scheme-program for computing this sequence.</a> %H A091227 <a href="/index/Ge#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a> %F A091227 a(n) = A091225(n) * A091226(n). %Y A091227 Inverse of A014580. a(n) = A049084(A091203(n)). %K A091227 nonn %O A091227 1,3 %A A091227 _Antti Karttunen_, Jan 03 2004