Expansion of (1-sqrt(1-4*(x+x^2)^2))/(2*(x+x^2)^2).

Terms

a(0) =1a(1) =0a(2) =1a(3) =2a(4) =3a(5) =8a(6) =17a(7) =38a(8) =91a(9) =212a(10) =509a(11) =1234a(12) =3007a(13) =7408a(14) =18353a(15) =45742a(16) =114643a(17) =288620a(18) =729749a(19) =1852138a(20) =4716951a(21) =12050920a(22) =30876185a(23) =79317990a(24) =204256027a(25) =527171556a(26) =1363428637a(27) =3533070818a(28) =9171798815a(29) =23849951200