G.f. A(x) satisfies A(x) = 1 - x/A(x)^4 * (1 - A(x) - A(x)^5).

Terms

a(0) =1a(1) =1a(2) =2a(3) =0a(4) =-6a(5) =12a(6) =67a(7) =-152a(8) =-740a(9) =2296a(10) =9017a(11) =-35979a(12) =-113936a(13) =579516a(14) =1454975a(15) =-9493390a(16) =-18317155a(17) =157178640a(18) =220172289a(19) =-2618995381a(20) =-2377680689a(21) =43783556265a(22) =19149194005a(23) =-732638868460a(24) =16196837316