Irregular triangle T read by rows: T(n, k) gives the number of permutations of [n] = {1, 2, ..., n} with a cycle of length m = floor(n/2) + k = A138099(n, k), for 1 <= k <= n - floor(n/2) = ceiling(n/2).

A364317

Irregular triangle T read by rows: T(n, k) gives the number of permutations of [n] = {1, 2, ..., n} with a cycle of length m = floor(n/2) + k = A138099(n, k), for 1 <= k <= n - floor(n/2) = ceiling(n/2).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =2a(4) =8a(5) =6a(6) =40a(7) =30a(8) =24a(9) =180a(10) =144a(11) =120a(12) =1260a(13) =1008a(14) =840a(15) =720a(16) =8064a(17) =6720a(18) =5760a(19) =5040a(20) =72576a(21) =60480a(22) =51840a(23) =45360a(24) =40320a(25) =604800a(26) =518400a(27) =453600a(28) =403200a(29) =362880

External references