G.f. 1/(1-z*R(z*m(z))) where R(z) = (1-z-(z+1)*sqrt(1-4*z))/(2*z^2), m(z) = (3-z-sqrt(1-6*z+z^2))/2.

A299296

G.f. 1/(1-z*R(z*m(z))) where R(z) = (1-z-(z+1)*sqrt(1-4*z))/(2*z^2), m(z) = (3-z-sqrt(1-6*z+z^2))/2.

Terms

    a(0) =1a(1) =2a(2) =7a(3) =30a(4) =140a(5) =684a(6) =3440a(7) =17652a(8) =91936a(9) =484356a(10) =2575280a(11) =13795668a(12) =74367408a(13) =403026372a(14) =2194186272a(15) =11993494356a(16) =65787201984a(17) =361983246084

External references