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

Terms

a(0) =1a(1) =1a(2) =-1a(3) =-2a(4) =-2a(5) =1a(6) =11a(7) =33a(8) =61a(9) =22a(10) =-418a(11) =-2363a(12) =-8375a(13) =-19715a(14) =-6325a(15) =263490a(16) =1950298a(17) =9423505a(18) =33042827a(19) =59212141a(20) =-283826231a(21) =-3970508822a(22) =-28167479326a(23) =-148668438363a(24) =-571280079455a(25) =-848399025239