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 A368023 #16 Dec 23 2023 12:55:35 %S A368023 1,42,35442,499114473,111384708171022,386735380538157813864, %T A368023 20749829798295730016646982120,17168067359133726591295713796489415774, %U A368023 219043020447199737063468653002456184101044391781,43136143328071407602633546712654262446417322619276001391870 %N A368023 a(n) is the permanent of the n-th order Hankel matrix of Catalan numbers M(n) whose generic element is given by M(i,j) = A000108(i+j+5) with i,j = 0, ..., n-1. %H A368023 Arthur T. Benjamin, Naiomi T. Cameron, Jennifer J. Quinn, and Carl R. Yerger, <a href="https://combinatorialpress.com/cn/arch/vol200/">Catalan determinants-a combinatorial approach</a>, Congressus Numerantium 200, 27-34 (2010). <a href="https://www.researchgate.net/publication/249812385_Catalan_determinants-a_combinatorial_approach">On ResearchGate</a>. %H A368023 M. E. Mays and Jerzy Wojciechowski, <a href="https://doi.org/10.1016/S0012-365X(99)00140-5">A determinant property of Catalan numbers</a>. Discrete Math. 211, No. 1-3, 125-133 (2000). %H A368023 Wikipedia, <a href="https://en.wikipedia.org/wiki/Hankel_matrix">Hankel matrix</a>. %F A368023 Det(M(n)) = A091962(n+1). %e A368023 a(4) = 111384708171022: %e A368023 42, 132, 429, 1430; %e A368023 132, 429, 1430, 4862; %e A368023 429, 1430, 4862, 16796; %e A368023 1430, 4862, 16796, 58786. %t A368023 Join[{1},Table[Permanent[Table[CatalanNumber[i+j+5],{i,0,n-1},{j,0,n-1}]],{n,10}]] %o A368023 (PARI) C(n) = binomial(2*n, n)/(n+1); \\ A000108 %o A368023 a(n) = matpermanent(matrix(n, n, i, j, C(i+j+3))); \\ _Michel Marcus_, Dec 11 2023 %Y A368023 Cf. A000108, A091962. %Y A368023 Cf. A278843, A368012, A368019, A368021, A368022, A368024, A368025. %Y A368023 Column k=5 of A368026. %K A368023 nonn %O A368023 0,2 %A A368023 _Stefano Spezia_, Dec 08 2023