a(n) = binomial(n + 4, 4)*9^n.

A173000

a(n) = binomial(n + 4, 4)*9^n.

Terms

    a(0) =1a(1) =45a(2) =1215a(3) =25515a(4) =459270a(5) =7440174a(6) =111602610a(7) =1578379770a(8) =21308126895a(9) =277005649635

External references