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

Terms

a(0) =1a(1) =2a(2) =2a(3) =8a(4) =22a(5) =80a(6) =268a(7) =976a(8) =3494a(9) =12896a(10) =47556a(11) =177744a(12) =666236a(13) =2515104a(14) =9525976a(15) =36240032a(16) =138269958a(17) =529193152a(18) =2030242708a(19) =7807266512a(20) =30082317460a(21) =116126074400a(22) =449014896040