19634136209domain: NAppears in sequencesa(n) = a(n-1) + a(n-2) + 2*a(n-3) with a(0)=2, a(1)=1, a(2)=5.at n=34A226308a(n) = (2*8^(n+1) - 9) / 7.at n=11A233328