18457556053domain: NAppears in sequencesExpansion of (2-3*x-x^2)/((1-x)*(1-2*x-x^2)).at n=27A052937Expansion of g.f. (1+8*x-x^2)/((1+x)*(1-6*x+x^2)).at n=13A105058a(n) = A000129(n) + (-1)^n.at n=28A111954Expansion of (1+x)*(2*x-1)/((1-x)*(x^2+2*x-1)).at n=28A174191a(n) = 6*a(n-1) - a(n-2) - 4 with n > 1, a(0)=1, a(1)=3.at n=14A182189