a(n) = (1)*(2 + 3 + 4 + ... + n) + (1 + 2)*(3 + 4 + 5 + ... + n) + (1 + 2 + 3)*(4 + 5 + 6 + ... + n) + ... + (1 + 2 + 3 + ... + n-1)*n.

A067056

a(n) = (1)*(2 + 3 + 4 + ... + n) + (1 + 2)*(3 + 4 + 5 + ... + n) + (1 + 2 + 3)*(4 + 5 + 6 + ... + n) + ... + (1 + 2 + 3 + ... + n-1)*n.

Terms

    a(0) =1a(1) =2a(2) =14a(3) =54a(4) =154a(5) =364a(6) =756a(7) =1428a(8) =2508a(9) =4158a(10) =6578a(11) =10010a(12) =14742a(13) =21112a(14) =29512a(15) =40392a(16) =54264a(17) =71706a(18) =93366a(19) =119966a(20) =152306a(21) =191268a(22) =237820a(23) =293020a(24) =358020a(25) =434070a(26) =522522a(27) =624834a(28) =742574a(29) =877424

External references