G.f. C(x) satisfies: C(x) = 1 + 2*x*A(x)*B(x) where A(x) = B(x)*C(x) and B(x) = 1 + x*A(x)*C(x).

A258315

G.f. C(x) satisfies: C(x) = 1 + 2*x*A(x)*B(x) where A(x) = B(x)*C(x) and B(x) = 1 + x*A(x)*C(x).

Terms

    a(0) =1a(1) =2a(2) =8a(3) =46a(4) =304a(5) =2178a(6) =16456a(7) =129086a(8) =1041248a(9) =8582274a(10) =71964232a(11) =611954286a(12) =5264786448a(13) =45741886786a(14) =400776143752

External references