2684354

Appears in sequences

• G.f.: A(x) = exp( Sum_{n>=1} sigma(n)*|A002129(n)|*x^n/n ).at n=25A162420
• a(n) = floor((-1 + 4^n)/(-1 + 2*n)).at n=12A191636
• a(n) = floor(2^(n+1)/n).at n=24A281375