A101821 Triangle read by rows: T(n,h) = number of functions f:{1,2,...,n}->{1,2,...,n-2} such that |Image(f)|=h, h=1,2,...,n-2; n=3,4,....

2, 3, 42, 4, 180, 600, 5, 620, 5400, 7800, 6, 1890, 36120, 126000, 100800, 7, 5534, 202860, 1428840, 2646000, 1340640, 8, 14280, 1016400, 13053600, 46710720, 53343360, 18627840, 9, 36792, 4702320, 103133520, 642978000, 1380576960

Offset: 0

Author

Clark Kimberling, Dec 17 2004

Keywords

• nonn
• tabl

Examples

			First rows:
2
3 42
4 180 600
5 620 5400 7800
		

Crossrefs

Cf. A019538, A101817, A101819.

Formula

T(n, h) = C(n-2, h)*U(n, h), where U(n, h) is the array in A019538.