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 A374675 #10 Jul 16 2024 11:34:30
%S A374675 1,2,21,244,3055,40116,544103,7553960,106734195,1528937200,
%T A374675 22143771386,323613807672,4765050473521,70611124679564,
%U A374675 1052084386116915,15750153504353872,236766112174722235,3572264808332407512,54073065371555283968,820886646834780680640
%N A374675 a(n) = Sum_{k=0..n} binomial(n+k-1,n) * binomial(n+k,n).
%F A374675 a(n) = Sum_{k=0..n} (k/(n+k)) * binomial(n+k,k)^2 for n > 0.
%F A374675 a(n) = (n+1) * A259335(n).
%o A374675 (PARI) a(n) = sum(k=0, n, binomial(n+k-1, n)*binomial(n+k, n));
%Y A374675 Cf. A001791, A374676.
%Y A374675 Cf. A112029, A129763, A259335.
%K A374675 nonn
%O A374675 0,2
%A A374675 _Seiichi Manyama_, Jul 16 2024