24517448581domain: NAppears in sequencesa(1)=1, a(n) = n*15^(n-1) + a(n-1).at n=8A0149301 + 2*n + 3*n^2 + 4*n^3 + 5*n^4 + 6*n^5 + 7*n^6 + 8*n^7 + 9*n^8.at n=15A113630