Let c(n) = x^(2^n-1)*(1-x^(2^n)), g(n) = 1 + x^(2^n-1) + x^(2^n), h(n) = Product_{i=1..n} g(i); then use g.f. (1+2*x) - Sum_{n>=1} c(n)/h(n).
A151684
Let c(n) = x^(2^n-1)*(1-x^(2^n)), g(n) = 1 + x^(2^n-1) + x^(2^n), h(n) = Product_{i=1..n} g(i); then use g.f. (1+2*x) - Sum_{n>=1} c(n)/h(n).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =0a(4) =-1a(5) =1a(6) =1a(7) =-1a(8) =0a(9) =0a(10) =-2a(11) =1a(12) =2a(13) =0a(14) =2a(15) =-1a(16) =-5a(17) =-1a(18) =1a(19) =3a(20) =7a(21) =1a(22) =-8a(23) =-8a(24) =-6a(25) =3a(26) =18a(27) =16a(28) =0a(29) =-17
External references
- oeis: A151684