a(n) = coefficient of x^n in the (n-1)-th iteration of Sum_{k>=0} x^(2^k), n>=1.

A168365

a(n) = coefficient of x^n in the (n-1)-th iteration of Sum_{k>=0} x^(2^k), n>=1.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =12a(4) =100a(5) =1070a(6) =14116a(7) =222614a(8) =4092964a(9) =86058372a(10) =2038072080a(11) =53704876742

External references