a(n) = (n^3+n)*9^n.A128074a(n) = (n^3+n)*9^n.Terms a(0) =0a(1) =18a(2) =810a(3) =21870a(4) =446148a(5) =7676370a(6) =117979902a(7) =1674039150a(8) =22384294920a(9) =285916320882External referencesoeis: A128074