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 A385725 #10 Jul 08 2025 07:47:22
%S A385725 1,1,1,1,1,6,31,106,281,3160,29701,176056,768241,12702704,173361371,
%T A385725 1466276176,8937060081,195180709248,3494232292681,38426220716416,
%U A385725 301057954180801,8174141246647552,181144607099402871,2452803139819922176,23494461553739152201,762800754226165963776
%N A385725 E.g.f. A(x) satisfies A(x) = exp( x*(A(x) + A(i*x) + A(-x) + A(-i*x))/4 ), where i is the imaginary unit.
%F A385725 a(0) = 1; a(n) = Sum_{k=0..floor((n-1)/4)} (4*k+1) * binomial(n-1,4*k) * a(4*k) * a(n-1-4*k).
%Y A385725 Cf. A000272, A058014, A385691.
%Y A385725 Cf. A118968.
%K A385725 nonn
%O A385725 0,6
%A A385725 _Seiichi Manyama_, Jul 08 2025