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 A379100 #8 Dec 15 2024 11:01:43 %S A379100 1,1,2,2,4,12,5,10,30,100,14,28,84,280,980,42,84,252,840,2940,10584, %T A379100 132,264,792,2640,9240,33264,121968,429,858,2574,8580,30030,108108, %U A379100 396396,1472328,1430,2860,8580,28600,100100,360360,1321320,4907760,18404100 %N A379100 Triangle read by rows: T(n, k) = binomial(2*k, k) * binomial(2*n, n) / (n + 1). %F A379100 T(n, k) = ((2*k)! * (2*n)!) / ((k! * n!)^2 * (n+1)). %e A379100 [0] 1; %e A379100 [1] 1, 2; %e A379100 [2] 2, 4, 12; %e A379100 [3] 5, 10, 30, 100; %e A379100 [4] 14, 28, 84, 280, 980; %e A379100 [5] 42, 84, 252, 840, 2940, 10584; %e A379100 [6] 132, 264, 792, 2640, 9240, 33264, 121968; %e A379100 [7] 429, 858, 2574, 8580, 30030, 108108, 396396, 1472328; %p A379100 T := (n, k) -> binomial(2*k, k) * binomial(2*n, n) / (n + 1): %p A379100 seq(seq(T(n, k), k = 0..n), n = 0..8); %Y A379100 Cf. A002894, A000888, A270577, A379099 (row sums). %K A379100 nonn,tabl %O A379100 0,3 %A A379100 _Peter Luschny_, Dec 15 2024