859446141837domain: NAppears in sequencesa(n) = 3*a(n-1) + a(n-2) with a(0) = 2, a(1) = 3.at n=23A006497Expansion of x*(3+x-x^3)/((1-3*x-x^2)*(1-x)*(1+x)).at n=23A212962Numbers n such that 13*n^2 + 52 is a square.at n=11A259131