T(n,k) is the number of partial bijections of height k (height(alpha) = |Im(alpha)|) of an n-element set.
A144084
T(n,k) is the number of partial bijections of height k (height(alpha) = |Im(alpha)|) of an n-element set.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =2a(6) =1a(7) =9a(8) =18a(9) =6a(10) =1a(11) =16a(12) =72a(13) =96a(14) =24a(15) =1a(16) =25a(17) =200a(18) =600a(19) =600a(20) =120a(21) =1a(22) =36a(23) =450a(24) =2400a(25) =5400a(26) =4320a(27) =720a(28) =1a(29) =49
External references
- oeis: A144084