466041domain: NAppears in sequencesa(n) = 3*a(n-2) + 2*a(n-3) for n > 2, a(0)=1, a(1)=0, a(2)=3.at n=20A053088a(n) = (4^(n+1) + 6n + 5)/9.at n=10A073724Expansion of (1 - x)^(-1)/(1 + x - 2*x^2).at n=20A077898a(0)=1, a(n)=2^n+n-2*a(n-1).at n=21A082383a(n) = a(n-1) + 3*a(n-2) - a(n-3) - 2*a(n-4), n > 3.at n=20A133993