Expansion of 1/(1-x^2*c(2*x)), c(x) the g.f. of A000108.

Terms

a(0) =1a(1) =0a(2) =1a(3) =2a(4) =9a(5) =44a(6) =245a(7) =1462a(8) =9157a(9) =59368a(10) =395033a(11) =2682282a(12) =18510561a(13) =129451492a(14) =915401757a(15) =6534282398a(16) =47020440413a(17) =340733200288