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 A137310 #2 Mar 30 2012 17:36:32 %S A137310 1,3,7,9,13,15,25,37,43,45,49,67,73,79,87,93,97,105,115,127,135,139, %T A137310 153,163,165,169,175,177,189,193,199,205,207,213,219,235,265,277,279, %U A137310 303,307,309,319,325,343,345,363,373,387,405,409,417,423,433,435,465,469 %N A137310 Numbers n such that a type-4 Gaussian normal basis over GF(2^n) exists. %C A137310 A type-t Gaussian normal basis exists for GF(2^n) if p=n*t+1 is prime and gcd(n,(p-1)/ord(2 mod p))==1. %Y A137310 Cf. A136415. %K A137310 nonn %O A137310 1,2 %A A137310 _Joerg Arndt_, Apr 05 2008