G.f. A(x) satisfies: A(x) = x - x^2 * A(x/(1 - x)) / (1 - x).

Terms

a(0) =0a(1) =1a(2) =0a(3) =-1a(4) =-2a(5) =-2a(6) =2a(7) =17a(8) =54a(9) =109a(10) =54a(11) =-796a(12) =-5000a(13) =-19499a(14) =-52252a(15) =-44617a(16) =577554a(17) =5071906a(18) =27330978a(19) =108557573a(20) =263947354a(21) =-453137963a(22) =-11252508862a(23) =-92193933208a(24) =-545809325184