cp's OEIS Frontend

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.

A368478 a(n) = [x^n] Product_{k=1..n} (x^(k^4) + 1 + 1/x^(k^4)).

This page as a plain text file.
%I A368478 #16 Jan 25 2024 19:58:14
%S A368478 1,1,0,0,0,0,0,0,0,0,0,0,3,22,88,236,568,1147,1999,3030,4333,4793,
%T A368478 5620,4628,9353,40048,312436,1638550,7894061,30866741,105342660,
%U A368478 323671449,863529149,2152428536,4750103818,9796453345,18572505806,32181800057,55712628236
%N A368478 a(n) = [x^n] Product_{k=1..n} (x^(k^4) + 1 + 1/x^(k^4)).
%p A368478 b:= proc(n, i) option remember; (m-> `if`(n>m, 0, `if`(n=m, 1, b(n, i-1)+
%p A368478       b(abs(n-i^4), i-1)+b(n+i^4, i-1))))(i*(i+1)*(2*i+1)*(3*i^2+3*i-1)/30)
%p A368478     end:
%p A368478 a:= n-> b(n$2):
%p A368478 seq(a(n), n=0..33);  # _Alois P. Heinz_, Jan 25 2024
%Y A368478 Cf. A000583, A316706, A369358, A369433, A369437.
%K A368478 nonn
%O A368478 0,13
%A A368478 _Ilya Gutkovskiy_, Jan 25 2024
%E A368478 a(34)-a(38) from _Alois P. Heinz_, Jan 25 2024