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 A307615 #8 Aug 09 2021 06:12:03
%S A307615 1,1,5,31,337,2741,40621,474475,8461601,132034537,2648537461,
%T A307615 50079699671,1204884343345,26450428964701,697107087763997,
%U A307615 17873985363570211,526080367468142401,15060611189639187665,487251625325328212581,15494976568071805188367,545902629556769672596241
%N A307615 E.g.f. A(x) satisfies: A(x) = exp(x) * A(x^2)^2*A(x^3)^3*A(x^4)^4* ... *A(x^k)^k* ...
%H A307615 Vaclav Kotesovec, <a href="/A307615/b307615.txt">Table of n, a(n) for n = 0..420</a>
%F A307615 E.g.f.: exp(Sum_{k>=1} A050369(k)*x^k).
%F A307615 a(0) = 1; a(n) = Sum_{k=1..n} A074206(k)*k*k!*binomial(n-1,k-1)*a(n-k).
%F A307615 a(n) ~ (-Gamma(2+r)/zeta'(r))^(1/(4 + 2*r)) * exp(-n + 12/25 + n^(1 - 1/(2+r)) * (2+r) * (-Gamma(2+r)/zeta'(r))^(1/(2+r)) / (1+r)) * n^(n - 1/(4 + 2*r)) / sqrt(2+r), where r = A107311 = 1.7286472389981836181351... is the root of the equation Zeta(r) = 2, Zeta'(r) = -1/A247667. - _Vaclav Kotesovec_, Aug 09 2021
%e A307615 E.g.f.: A(x) = 1 + x + 5*x^2/2! + 31*x^3/3! + 337*x^4/4! + 2741*x^5/5! + 40621*x^6/6! + 474475*x^7/7! + 8461601*x^8/8! + 132034537*x^9/9! + ...
%t A307615 terms = 20; A[_] = 1; Do[A[x_] = Exp[x] Product[A[x^k]^k, {k, 2, terms}] + O[x]^(terms + 1) // Normal, terms + 1]; CoefficientList[A[x], x] Range[0, terms]!
%Y A307615 Cf. A050369, A074206, A129375, A307604.
%K A307615 nonn
%O A307615 0,3
%A A307615 _Ilya Gutkovskiy_, Apr 18 2019