G.f. A(x) satisfies: A(x)^2 = 1/AGM(1, 1 - 8*x/A(x)^2 ).

Terms

a(0) =1a(1) =2a(2) =0a(3) =0a(4) =2a(5) =-4a(6) =0a(7) =0a(8) =-16a(9) =40a(10) =0a(11) =0a(12) =200a(13) =-544a(14) =0a(15) =0a(16) =-3006a(17) =8540a(18) =0a(19) =0a(20) =49956a(21) =-145720a(22) =0a(23) =0a(24) =-884352a(25) =2625648a(26) =0a(27) =0a(28) =16349648a(29) =-49161024