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 A359648 #8 Jan 18 2023 09:34:23 %S A359648 1,1,1,1,2,1,3,9,9,3,2,8,12,8,2,10,50,100,100,50,10,5,30,75,100,75,30, %T A359648 5,35,245,735,1225,1225,735,245,35,14,112,392,784,980,784,392,112,14, %U A359648 126,1134,4536,10584,15876,15876,10584,4536,1134,126 %N A359648 Triangle read by rows. T(n, k) = (n!)^2 / (k! * (n - k)! * (floor(n/2)!)^2 * (floor(n/2) + 1)). %F A359648 T(n, k) = binomial(n, k) * A057977(n). %e A359648 Triangle T(n, k) starts: %e A359648 [0] 1; %e A359648 [1] 1, 1; %e A359648 [2] 1, 2, 1; %e A359648 [3] 3, 9, 9, 3; %e A359648 [4] 2, 8, 12, 8, 2; %e A359648 [5] 10, 50, 100, 100, 50, 10; %e A359648 [6] 5, 30, 75, 100, 75, 30, 5; %e A359648 [7] 35, 245, 735, 1225, 1225, 735, 245, 35; %e A359648 [8] 14, 112, 392, 784, 980, 784, 392, 112, 14; %e A359648 [9] 126, 1134, 4536, 10584, 15876, 15876, 10584, 4536, 1134, 126; %p A359648 T := proc(n, k) n!^2 / (k! * (n - k)! * iquo(n,2)!^2 * (iquo(n,2) + 1)) end: %p A359648 for n from 0 to 9 do seq(T(n, k), k = 0..n) od; %Y A359648 Cf. A057977, A063549, A240558 (row sums), A000007 (alternating row sums). %K A359648 nonn,tabl %O A359648 0,5 %A A359648 _Peter Luschny_, Jan 09 2023