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 A363660 #17 Jul 17 2023 00:58:25
%S A363660 2,9,24,90,258,1043,3440,13419,48850,187836,705444,2725099,10400614,
%T A363660 40233015,155133856,601820876,2333606238,9079958260,35345263820,
%U A363660 137876637843,538259060526,2104292500739,8233430727624,32248866496625,126410606580284
%N A363660 a(n) = Sum_{d|n} binomial(d+n,n).
%F A363660 a(n) = [x^n] Sum_{k>0} (1/(1 - x^k)^(n+1) - 1).
%F A363660 a(n) = [x^n] Sum_{k>0} binomial(k+n,n) * x^k/(1 - x^k).
%t A363660 a[n_] := DivisorSum[n, Binomial[# + n, n] &]; Array[a, 25] (* _Amiram Eldar_, Jul 17 2023 *)
%o A363660 (PARI) a(n) = sumdiv(n, d, binomial(d+n, n));
%Y A363660 Cf. A007503, A116963, A363628.
%Y A363660 Cf. A000984, A134758, A343548, A343549, A363661.
%K A363660 nonn
%O A363660 1,1
%A A363660 _Seiichi Manyama_, Jun 14 2023