Triangle read by rows: T(n,k) = (k+1)*T(n-1,k) + (n-k+1)*T(n,k-1).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =4a(6) =1a(7) =11a(8) =34a(9) =34a(10) =1a(11) =26a(12) =180a(13) =496a(14) =496a(15) =1a(16) =57a(17) =768a(18) =4288a(19) =11056a(20) =11056a(21) =1a(22) =120a(23) =2904a(24) =28768a(25) =141584a(26) =349504a(27) =349504a(28) =1a(29) =247