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 A324597 #19 Dec 15 2024 15:46:35 %S A324597 1,2,918,11592504000,86712397842439769400000, %T A324597 3472997049383321958747830928094241894400000, %U A324597 4152034082374349458781848863476555783741415883758270213129361920000000 %N A324597 a(n) = n!^(4*n) * Product_{k=1..n} binomial(n + 1/k^3, n). %C A324597 In general, for m > 1, Product_{k=1..n} binomial(n + 1/k^m, n) ~ n^Zeta(m) / c(m), where c(m) = Product_{j>=1} Gamma(1 + 1/j^m). %C A324597 Equivalently, c(m) = -gamma * Zeta(m) + Sum_{k>=2} (-1)^k*Zeta(k)*Zeta(m*k)/k, where gamma is the Euler-Mascheroni constant A001620. %F A324597 a(n) ~ n!^(4*n) * n^Zeta(3) / (Product_{j>=1} Gamma(1 + 1/j^3)). %F A324597 a(n) ~ n^(4*n^2 + 2*n + Zeta(3)) * (2*Pi)^(2*n) / exp(4*n^2 - 1/3 - gamma*Zeta(3) + c), where c = A306778 = Sum_{k>=2} (-1)^k*Zeta(k)*Zeta(3*k)/k. %p A324597 a:= n-> n!^(4*n)*mul(binomial(n+1/k^3, n), k=1..n): %p A324597 seq(a(n), n=0..7); # _Alois P. Heinz_, Jun 24 2023 %t A324597 Table[n!^(4*n) * Product[Binomial[n + 1/j^3, n], {j, 1, n}], {n, 1, 8}] %Y A324597 Cf. A306760, A324596, A306778. %K A324597 nonn %O A324597 0,2 %A A324597 _Vaclav Kotesovec_, Mar 09 2019 %E A324597 a(0)=1 prepended by _Alois P. Heinz_, Jun 24 2023