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 A374891 #7 Aug 02 2024 18:59:44
%S A374891 2,6,42,882,62622,15843366,14655113550,50311004817150,
%T A374891 647552943001537650,31484671641677762080650,
%U A374891 5817013478501458288734652050,4103513269179719224996951799587650,11096544131445222000310082187517540861050
%N A374891 Obverse convolution (1)**A000984; see Comments.
%C A374891 See A374848 for the definition of obverse convolution and a guide to related sequences. This is a divisibility sequence (see Formula).
%F A374891 a(n+1) = a(n)*A244174(n+1) for n>=0 (conjectured) = a(n)*A323230(n+2) for n>=0 (conjectured).
%F A374891 a(n) ~ c * A007685(n), where c = Product_{k=0..oo} (1 + 1/binomial(2*k,k)) = 3.74782908533723753117687910314018231428739915473496578523053032212205053... - _Vaclav Kotesovec_, Jul 31 2024
%t A374891 s[n_] := 1; t[n_] := Binomial[2 n, n];
%t A374891 u[n_] := Product[s[k] + t[n - k], {k, 0, n}]
%t A374891 Table[u[n], {n, 0, 20}]
%Y A374891 Cf. A000012, A000984, A007685, A374848.
%K A374891 nonn
%O A374891 0,1
%A A374891 _Clark Kimberling_, Jul 31 2024