Triangular array read by rows. T(n,k) is the number of partial functions f on [n] such that there are exactly k points in [n] that are neither in the domain of f nor in the image of f, n>=0, 0<=k<=n.
A377763
Triangular array read by rows. T(n,k) is the number of partial functions f on [n] such that there are exactly k points in [n] that are neither in the domain of f nor in the image of f, n>=0, 0<=k<=n.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =6a(4) =2a(5) =1a(6) =42a(7) =18a(8) =3a(9) =1a(10) =416a(11) =168a(12) =36a(13) =4a(14) =1a(15) =5210a(16) =2080a(17) =420a(18) =60a(19) =5a(20) =1a(21) =79212a(22) =31260a(23) =6240a(24) =840a(25) =90a(26) =6a(27) =1a(28) =1417094a(29) =554484
External references
- oeis: A377763