21695547384domain: NAppears in sequencesa(n) = Sum_{k=0..m} (k+1) * A026082(n, k), where 0 <= k <= m, m=n for n=0,1,2,3; m=2n for n >= 4.at n=20A027319a(n) = (n^3 - n)*9^n.at n=7A128969