2460160domain: NAppears in sequencesa(n) = 9*a(n-1) - 9*a(n-2) + a(n-3); given a(1) = 1, a(2) = 10, a(3) = 81.at n=7A095004a(n) = C(n,a)*C(n,b)*C(n,c)... where n = abc... are the decimal digits of n.at n=31A111695