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 A158801 #7 Jul 21 2018 15:53:05 %S A158801 0,0,0,2,0,0,0,8,0,0,0,6,0,0,0,14,0,0,0,6,0,0,0,24,0,0,0,6,0,0,0,20,0, %T A158801 0,0,12,0,0,0,24,0,0,0,6,0,0,0,42,0,0,0,6,0,0,0,24,0,0,0,18,0,0,0,26, %U A158801 0,0,0,6,0,0,0,48,0,0,0,6,0,0,0,42,0,0,0,18,0,0,0,24,0,0,0,6,0,0,0,60,0,0,0 %N A158801 a(n) = A145444(n) - A145501(n). %H A158801 Antti Karttunen, <a href="/A158801/b158801.txt">Table of n, a(n) for n = 1..65537</a> %o A158801 (PARI) %o A158801 up_to = 1001; %o A158801 t1=direuler(p=2, up_to, 1/(1-X)^3); %o A158801 t2=direuler(p=2, 2, 1+3*X^2+2*X^3, up_to); %o A158801 t3=dirmul(t1, t2); \\ For A145444 %o A158801 u1=direuler(p=2, up_to, 1/(1-X)^3); %o A158801 u2=direuler(p=2, 2, 1+1*X^2+4*X^4, up_to); %o A158801 u3=dirmul(u1, u2); \\ For A145501 %o A158801 A158801(n) = (t3[n]-u3[n]); \\ _Antti Karttunen_, Jul 21 2018 %Y A158801 See A145444, A145501, A145511, A158334. %K A158801 nonn %O A158801 1,4 %A A158801 _Paul Curtz_, Mar 27 2009 %E A158801 Edited and extended by _R. J. Mathar_, Apr 08 2009