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 A026958 #15 Jun 18 2024 11:09:17
%S A026958 1,10,69,340,1476,6074,24419,97136,384428,1517422,5981070,23556746,
%T A026958 92743296,365078146,1437124303,5657887016,22279053380,87749051950,
%U A026958 345704345066,1362361338578,5370436417996,21176724230654,83529562154498,329573910914930,1300752571946396
%N A026958 a(n) = Sum_{k=0..n-2} T(n,k) * T(n,k+2), with T given by A026615.
%H A026958 G. C. Greubel, <a href="/A026958/b026958.txt">Table of n, a(n) for n = 2..1000</a>
%F A026958 a(n) = binomial(2*n, n+2)*(49*n^4 - 154*n^3 + 209*n^2 - 200*n + 108)/(24*binomial(2*n, 4)) -2*(n^2 - 2*n + 2) + [n=2]. - _G. C. Greubel_, Jun 17 2024
%t A026958 Table[Binomial[2*n,n+2]*(49*n^4 -154*n^3 +209*n^2 -200*n +108)/(24* Binomial[2*n,4]) -2*(n^2-2*n+2) + Boole[n==2], {n,2,40}] (* _G. C. Greubel_, Jun 17 2024 *)
%o A026958 (Magma) [n eq 2 select 1 else Binomial(2*n,n+2)*(49*n^4 -154*n^3 + 209*n^2 -200*n +108)/(24*Binomial(2*n,4)) -2*(n^2-2*n+2): n in [2..40]]; // _G. C. Greubel_, Jun 17 2024
%o A026958 (SageMath) [binomial(2*n,n+2)*(49*n^4 -154*n^3 +209*n^2 -200*n +108 )/(24*binomial(2*n,4)) -2*(n^2-2*n+2) +int(n==2) for n in range(2,41)] # _G. C. Greubel_, Jun 17 2024
%Y A026958 Cf. A026615, A026616, A026617, A026618, A026619, A026620, A026621.
%Y A026958 Cf. A026622, A026623, A026624, A026625, A026956, A026957, A026959.
%Y A026958 Cf. A026960.
%K A026958 nonn
%O A026958 2,2
%A A026958 _Clark Kimberling_
%E A026958 More terms from _Sean A. Irvine_, Oct 20 2019