Recursive triangular symmetrical sequence: A(n,k) := (n - k + 1)A(n - 1, k - 1) + (k)* A(n - 1, k) - (n + 1)*A(n - 2, k - 1).

A153479

Recursive triangular symmetrical sequence: A(n,k) := (n - k + 1)A(n - 1, k - 1) + (k)* A(n - 1, k) - (n + 1)*A(n - 2, k - 1).

Terms

    a(0) =2a(1) =3a(2) =3a(3) =2a(4) =14a(5) =2a(6) =2a(7) =25a(8) =25a(9) =2a(10) =2a(11) =46a(12) =66a(13) =46a(14) =2a(15) =2a(16) =88a(17) =207a(18) =207a(19) =88a(20) =2a(21) =2a(22) =172a(23) =693a(24) =1128a(25) =693a(26) =172a(27) =2a(28) =2a(29) =340

External references