Expansion of 1/(1 - 4 * Sum_{k>=0} x^(3^k))^(1/2).

Terms

a(0) =1a(1) =2a(2) =6a(3) =22a(4) =82a(5) =312a(6) =1210a(7) =4752a(8) =18834a(9) =75186a(10) =301868a(11) =1217664a(12) =4930918a(13) =20033432a(14) =81621456a(15) =333357656a(16) =1364395770a(17) =5594799576a(18) =22980090870a(19) =94529049296a(20) =389367825444