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 A342972 #34 Apr 03 2021 08:38:46 %S A342972 1,1,1,1,3,1,1,10,10,1,1,35,105,35,1,1,126,1176,1176,126,1,1,462, %T A342972 13860,41580,13860,462,1,1,1716,169884,1557270,1557270,169884,1716,1, %U A342972 1,6435,2147145,61408347,184225041,61408347,2147145,6435,1 %N A342972 Triangle T(n,k) read by rows: T(n,k) = Product_{j=0..n-1} binomial(n+j,k)/binomial(k+j,k). %C A342972 Triangle read by rows: T(n,k) = generalized binomial coefficients (n,k)_n where (n,k)_m is Product_{j=1..k} binomial(n-j+m,m)/binomial(j-1+m,m). %H A342972 Seiichi Manyama, <a href="/A342972/b342972.txt">Rows n = 0..50, flattened</a> %F A342972 T(n,k) = Product_{j=0..k-1} binomial(2*n-1,n+j)/binomial(2*n-1,j). %e A342972 Triangle begins: %e A342972 1; %e A342972 1, 1; %e A342972 1, 3, 1; %e A342972 1, 10, 10, 1; %e A342972 1, 35, 105, 35, 1; %e A342972 1, 126, 1176, 1176, 126, 1; %e A342972 1, 462, 13860, 41580, 13860, 462, 1; %e A342972 1, 1716, 169884, 1557270, 1557270, 169884, 1716, 1; %e A342972 1, 6435, 2147145, 61408347, 184225041, 61408347, 2147145, 6435, 1; %t A342972 T[n_, k_] := Product[Binomial[n + i, k]/Binomial[k + i, k], {i, 0, n - 1}]; Table[T[n, k], {n, 0, 8}, {k, 0, n}] // Flatten (* _Amiram Eldar_, Apr 01 2021 *) %o A342972 (PARI) T(n, k) = prod(j=0, n-1, binomial(n+j, k)/binomial(k+j, k)); %o A342972 (PARI) T(n, k) = prod(j=0, k-1, binomial(2*n-1, n+j)/binomial(2*n-1, j)); %o A342972 (PARI) f(n, k, m) = prod(j=1, k, binomial(n-j+m, m)/binomial(j-1+m, m)); %o A342972 T(n, k) = f(n, k, n); %Y A342972 Row sums gives A342967. %Y A342972 Triangles of generalized binomial coefficients (n,k)_m (or generalized Pascal triangles) for m = 1,...,12: A007318 (Pascal), A001263, A056939, A056940, A056941, A142465, A142467, A142468, A174109, A342889, A342890, A342891. %K A342972 nonn,tabl %O A342972 0,5 %A A342972 _Seiichi Manyama_, Apr 01 2021