Triangle T(n,k) = (2*n-k-1)*T(n-1,k-1) + (k+1)*T(n-1,k), with T(n,1) = T(n,n) = 1, 1 <= k <= n, read by rows.
A156139
Triangle T(n,k) = (2*n-k-1)*T(n-1,k-1) + (k+1)*T(n-1,k), with T(n,1) = T(n,n) = 1, 1 <= k <= n, read by rows.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =6a(5) =1a(6) =1a(7) =23a(8) =28a(9) =1a(10) =1a(11) =76a(12) =250a(13) =145a(14) =1a(15) =1a(16) =237a(17) =1608a(18) =2475a(19) =876a(20) =1a(21) =1a(22) =722a(23) =8802a(24) =26847a(25) =25056a(26) =6139a(27) =1a(28) =1a(29) =2179
External references
- oeis: A156139