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 A091546 #13 Aug 30 2025 02:43:26
%S A091546 1,56,10192,3872960,2517424000,2497284608000,3511182158848000,
%T A091546 6643156644540416000,16275733779124019200000,
%U A091546 50129260039701979136000000,189588861470152885092352000000,863766852858016544480755712000000,4666068539139005373285042356224000000,29489553167358513959161467691335680000000
%N A091546 First column of the array A092077 ((8,2)-Stirling2).
%C A091546 Also seventh column (m=6) of triangle A091543.
%H A091546 Pawel Blasiak, Karol A. Penson, and Allan I. Solomon, <a href="https://doi.org/10.1016/S0375-9601(03)00194-4">The general boson normal ordering problem</a>, Physics Letters A, Vol. 309, No. 3-4 (2003), pp. 198-205; <a href="https://arxiv.org/abs/quant-ph/0402027">arXiv preprint</a>, arXiv:quant-ph/0402027, 2004.
%F A091546 a(n) = (2^(n-1))*Product_{j=0..n-1} ((3*j+1)*(6*j+1)), n>=1. From eq.12 of the Blasiak et al. reference with r=8, s=2, k=1.
%F A091546 a(n) = (6^(2*n))*risefac(1/6, n)*risefac(1/3, n)/2, n>=1, with risefac(x, n) = Pochhammer(x, n).
%F A091546 a(n) = fac6(6*n-5)*fac6(6*n-4)/2, n>=1, with fac6(6*n-5) = A008542(n) and fac6(6*n-4)/2 = A034689(n)= (2^(n-1))*A007559(n), (6-factorials).
%F A091546 a(n) ~ Pi * (6/e)^(2*n) * n^(2*n-1/2) / (Gamma(1/6) * Gamma(1/3)). - _Amiram Eldar_, Aug 30 2025
%t A091546 a[n_] := 6^(2*n) * Pochhammer[1/6, n] * Pochhammer[1/3, n] / 2; Array[a, 20] (* _Amiram Eldar_, Aug 30 2025 *)
%Y A091546 Cf. A007559, A008542, A034689, A091543, A092077.
%Y A091546 Cf. A073005, A175379.
%K A091546 nonn,easy,changed
%O A091546 1,2
%A A091546 _Wolfdieter Lang_, Feb 13 2004