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 A091230 #30 Aug 08 2014 08:59:18 %S A091230 1,2,3,7,25,137,1123,13103,204045,4050293,99440273 %N A091230 Iterates of A014580, starting with a(0) = 1, a(n) = A014580^(n)(1). [Here A014580^(n) means the n-th fold application of A014580]. %H A091230 A. Karttunen, <a href="/A091247/a091247.scm.txt">Scheme-program for computing this sequence.</a> %H A091230 <a href="/index/Ge#GF2X">Index entries for sequences operating on GF(2)[X]-polynomials</a> %F A091230 a(0)=1, a(n) = A014580(a(n-1)). [The defining recurrence]. %F A091230 From _Antti Karttunen_, Aug 03 2014: (Start) %F A091230 Other identities. For all n >= 0, the following holds: %F A091230 A091238(a(n)) = n+1. %F A091230 a(n) = A091204(A007097(n)) and A091205(a(n)) = A007097(n). %F A091230 a(n) = A245703(A007097(n)) and A245704(a(n)) = A007097(n). %F A091230 a(n) = A245702(A000079(n)) and A245701(a(n)) = A000079(n). %F A091230 (End) %o A091230 (PARI) %o A091230 isA014580(n)=polisirreducible(Pol(binary(n))*Mod(1, 2)); \\ This function from _Charles R Greathouse IV_ %o A091230 prev=1; i=0; print1(1, ", "); for(n=1, 123456789, if(isA014580(n), i++; if((i == prev), print1(n, ", "); prev=n))) \\ _Antti Karttunen_, Aug 02 2014 %Y A091230 Cf. A000079, A007097, A091238, A091204-A091205, A245701-A245702, A245703-A245704. %K A091230 nonn %O A091230 0,2 %A A091230 _Antti Karttunen_, Jan 03 2004 %E A091230 Terms a(8)-a(10) computed by _Antti Karttunen_, Aug 02 2014