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 A113857 #14 Sep 05 2025 02:01:23
%S A113857 126,2772,48048,772200,12033450,184940756,2824549728,43028530272,
%T A113857 655081791000,9977399586000,152112583402560,2322021633001200,
%U A113857 35496198345658050,543418421128852500,8331507823355640000,127919340117331963200,1966759854303978934200,30279186980267369086800
%N A113857 a(n) = binomial(4+2*n, n) * binomial(9+2*n, 4+n).
%C A113857 If one uses the "table" view of array A062190, the sequence appears as the fourth column right from the middle in the "formatted as a triangular array" subpanel.
%H A113857 Andrew Howroyd, <a href="/A113857/b113857.txt">Table of n, a(n) for n = 0..200</a>
%F A113857 a(n) = A062190(4+2*n, 4+n).
%F A113857 a(n) = A002694(n+2)*A001700(n+4). - _R. J. Mathar_, Nov 28 2008
%F A113857 a(n) ~ 2^(4*n+13) / (Pi*n). - _Amiram Eldar_, Sep 05 2025
%e A113857 a(0) = C(4+2*n,n)*C(9+2*n,4+n) = C(4,0)*C(9,4) = 1*126 = 126.
%e A113857 a(7) = C(4+2*7,7)*C(9+2*7,4+7) = C(18,7)*C(23,11) = 31824*1352078 = 43028530272.
%t A113857 a[n_] := Binomial[4+2*n, n] * Binomial[9+2*n, 4+n]; Array[a, 20, 0] (* _Amiram Eldar_, Sep 05 2025 *)
%o A113857 (PARI) a(n)={binomial(4+2*n, n) * binomial(9+2*n, 4+n)} \\ _Andrew Howroyd_, Jan 07 2020
%Y A113857 Cf. A001700, A002694, A062190.
%K A113857 easy,nonn,changed
%O A113857 0,1
%A A113857 _Zerinvary Lajos_, Feb 02 2006
%E A113857 Definition rephrased by _R. J. Mathar_, Nov 28 2008
%E A113857 Edited and more terms added by _Andrew Howroyd_, Jan 07 2020