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

Terms

a(0) =1a(1) =2a(2) =6a(3) =20a(4) =72a(5) =272a(6) =1064a(7) =4272a(8) =17504a(9) =72896a(10) =307648a(11) =1312896a(12) =5655808a(13) =24562176a(14) =107419264a(15) =472675072a(16) =2091206144a(17) =9296612352a(18) =41507566592a(19) =186045061120a(20) =836830457856