a(n) = (-1)^n * Sum_{i=0..n} binomial(n+1,i+1)*Catalan(i).

Terms

a(0) =1a(1) =-3a(2) =8a(3) =-23a(4) =74a(5) =-262a(6) =993a(7) =-3943a(8) =16178a(9) =-68000a(10) =291191a(11) =-1265618a(12) =5568263a(13) =-24749363a(14) =110961248a(15) =-501209303a(16) =2278704938a(17) =-10419244888a(18) =47882934663a(19) =-221047167628