-4245504

Appears in sequences

• E.g.f.: 2*x/(1+exp(-2*x)).at n=12A109573
• a(n) = n*4^n*(-Z(1-n, 1/4)/2 + Z(1-n, 3/4)/2 - Z(1-n, 1)*(1 - 2^(-n))) for n > 0 and a(0) = 0, where Z(n, c) is the Hurwitz zeta function.at n=12A243963