1040068261domain: NAppears in sequencesa(n) = 6*a(n-2) - a(n-4).at n=25A006452a(n) = 6*a(n-1) - a(n-2), n >= 2, a(0)=1, a(1)=4.at n=12A038723Expansion of (1 + 6*x + 17*x^2 - x^3 - 3*x^4)/(1 - 6*x^2 + x^4).at n=22A227792a(n) = sqrt(A299921(n)).at n=37A301318