G.f. A(x) satisfies: A(x) = A(x^2)^(1/2) + 4*x.

Terms

a(0) =1a(1) =4a(2) =2a(3) =0a(4) =-1a(5) =0a(6) =2a(7) =0a(8) =-5a(9) =0a(10) =12a(11) =0a(12) =-30a(13) =0a(14) =82a(15) =0a(16) =-233a(17) =0a(18) =668a(19) =0a(20) =-1949a(21) =0a(22) =5802a(23) =0a(24) =-17503a(25) =0a(26) =53302a(27) =0a(28) =-163783a(29) =0