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 A278239 #6 Nov 19 2016 08:30:03 %S A278239 1,4,6,16,12,60,6,64,30,180,6,240,12,60,24,256,240,420,6,720,12,60,30, %T A278239 960,6,180,60,240,30,360,30,1024,30,5040,30,1680,6,60,360,2880,30,180, %U A278239 210,240,120,420,6,3840,60,60,96,720,210,1260,6,960,60,420,30,2160,12,420,60,4096,180,420,30,45360,60,420,30,6720,30,60,840,240,30,12600,30,11520,12 %N A278239 a(n) = A278233(A277699(n)). %C A278239 Prime factorization sentinel computed for A277699. Factorization is essentially done in the polynomial ring GF(2)[X]. %H A278239 Antti Karttunen, <a href="/A278239/b278239.txt">Table of n, a(n) for n = 1..256</a> %H A278239 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a> %H A278239 <a href="/index/Ge#GF2X">Index entries for sequences operating on polynomials in ring GF(2)[X]</a> %F A278239 a(n) = A278233(A277699(n)). %o A278239 (Scheme) (define (A278239 n) (A278233 (A277699 n))) %Y A278239 Cf. A048720, A065621, A277320, A277699, A278233, A278238. %K A278239 nonn %O A278239 1,2 %A A278239 _Antti Karttunen_, Nov 17 2016