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,....

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,....

Terms

    a(0) =2a(1) =3a(2) =42a(3) =4a(4) =180a(5) =600a(6) =5a(7) =620a(8) =5400a(9) =7800a(10) =6a(11) =1890a(12) =36120a(13) =126000a(14) =100800a(15) =7a(16) =5534a(17) =202860a(18) =1428840a(19) =2646000a(20) =1340640a(21) =8a(22) =14280a(23) =1016400a(24) =13053600a(25) =46710720a(26) =53343360a(27) =18627840a(28) =9a(29) =36792

External references