82781215domain: NAppears in sequencesa(n) = (Fibonacci(2n-1) - Fibonacci(n+1))/2.at n=21A056014Constant term of the reduction of the polynomial p(n,x)=(1/2)((x+1)^n+(x-1)^n) by x^2->x+1.at n=21A192352Number of orbits of size 2 in vertices of Fibonacci cube Gamma_n under the action of its automorphism group.at n=38A250111