Number of compositions of n into exactly n nonnegative parts <= seven.

Terms

a(0) =1a(1) =1a(2) =3a(3) =10a(4) =35a(5) =126a(6) =462a(7) =1716a(8) =6427a(9) =24229a(10) =91828a(11) =349570a(12) =1335698a(13) =5119856a(14) =19678452a(15) =75814560a(16) =292695291a(17) =1132074847a(18) =4385740683a(19) =17015510820a(20) =66102536360a(21) =257103599280