143489070domain: NAppears in sequencesa(n) = 10*3^n.at n=15A005052Diagonal of table A062104.at n=18A062107Expansion of 1/(3*x^2 - 3*x + 1)^2.at n=27A115052a(n) = 2*n*3^(n-1).at n=14A212697