Numerator of the n-th convergent to Sum_{k>=0} 1/2^(2^k).

Terms

a(0) =0a(1) =1a(2) =4a(3) =9a(4) =40a(5) =169a(6) =1054a(7) =4385a(8) =9824a(9) =43681a(10) =271910a(11) =587501a(12) =2621914a(13) =16318985a(14) =67897854a(15) =287910401a(16) =643718656a(17) =2862785025a(18) =17820428806a(19) =38503642637a(20) =171834999354a(21) =725843640053