Expansion of g.f.: (1-3*x*C)/(1-4*x*C) where C = (1 - sqrt(1-4*x))/(2*x) = g.f. for Catalan numbers A000108.

A076025

Expansion of g.f.: (1-3*x*C)/(1-4*x*C) where C = (1 - sqrt(1-4*x))/(2*x) = g.f. for Catalan numbers A000108.

Terms

    a(0) =1a(1) =1a(2) =5a(3) =26a(4) =137a(5) =726a(6) =3858a(7) =20532a(8) =109361a(9) =582782a(10) =3106550a(11) =16562668a(12) =88314634a(13) =470942044a(14) =2511443268a(15) =13393472616a(16) =71428622337a(17) =380940866574

External references