Triangular array T(n,k): functions f:{1,2,...,n}-> {1,2,...,n} such that each of k fixed (but arbitrary) elements are in the image of f.
A174551
Triangular array T(n,k): functions f:{1,2,...,n}-> {1,2,...,n} such that each of k fixed (but arbitrary) elements are in the image of f.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =4a(4) =3a(5) =2a(6) =27a(7) =19a(8) =12a(9) =6a(10) =256a(11) =175a(12) =110a(13) =60a(14) =24a(15) =3125a(16) =2101a(17) =1320a(18) =750a(19) =360a(20) =120a(21) =46656a(22) =31031a(23) =19502a(24) =11340a(25) =5880a(26) =2520a(27) =720a(28) =823543a(29) =543607
External references
- oeis: A174551