Triangular array read by rows. T(n,k) is the number of partial permutations (injective partial functions) of {1,2,...,n} that have exactly k elements in a cycle. The k elements are not necessarily in the same cycle. A fixed point is considered to be in a cycle.

A206703

Triangular array read by rows. T(n,k) is the number of partial permutations (injective partial functions) of {1,2,...,n} that have exactly k elements in a cycle. The k elements are not necessarily in the same cycle. A fixed point is considered to be in a cycle.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =3a(4) =2a(5) =2a(6) =13a(7) =9a(8) =6a(9) =6a(10) =73a(11) =52a(12) =36a(13) =24a(14) =24a(15) =501a(16) =365a(17) =260a(18) =180a(19) =120a(20) =120a(21) =4051a(22) =3006a(23) =2190a(24) =1560a(25) =1080a(26) =720a(27) =720a(28) =37633a(29) =28357

External references