Triangular array read by rows: T(n, k) is the number of rooted forests on {1, 2, ..., n} in which one tree has been specially designated that contain exactly k trees; n >= 1, 1 <= k <= n.

A225465

Triangular array read by rows: T(n, k) is the number of rooted forests on {1, 2, ..., n} in which one tree has been specially designated that contain exactly k trees; n >= 1, 1 <= k <= n.

Terms

    a(0) =1a(1) =2a(2) =2a(3) =9a(4) =12a(5) =3a(6) =64a(7) =96a(8) =36a(9) =4a(10) =625a(11) =1000a(12) =450a(13) =80a(14) =5a(15) =7776a(16) =12960a(17) =6480a(18) =1440a(19) =150a(20) =6a(21) =117649a(22) =201684a(23) =108045a(24) =27440a(25) =3675a(26) =252a(27) =7a(28) =2097152a(29) =3670016

External references