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 A013701 #10 Aug 21 2020 09:12:34
%S A013701 1,512,75025,7174454,562110290,39541748736,2610763825782,
%T A013701 165745451110910,10262482704258873,625250747214775916,
%U A013701 37701606156514031251,2258713106034310399852,134810129909509070121060
%N A013701 Degree of variety K_{2,n}^4.
%C A013701 Number of Catalan paths (nonnegative, starting and ending at 0, step +/-1) of 6n+8 steps with all values less than or equal to n+1 (see A080934).
%H A013701 M. S. Ravi et al., <a href="https://doi.org/10.1137/S036301299325270X">Dynamic pole assignment and Schubert calculus</a>, SIAM J. Control Optimization, 34 (1996), 813-832, esp. p. 825.
%o A013701 (PARI) K(n,q=4)=(2*n+n*q+2*q)!*sum(j=0,q,((q-2*j)*(n+2)+1)/(n+j*(n+2))!/(n+1+(q-j)*(n+2))!)
%Y A013701 Cf. A013698 (q=1), A013699 (q=2), A013700 (q=3), A013702 (q=5).
%K A013701 nonn,easy
%O A013701 1,2
%A A013701 Joachim.Rosenthal(AT)nd.edu (Joachim Rosenthal)