2969432270domain: NAppears in sequencesNumber of solutions to +-1 +- 3 +- 5 +- 7 +- ... +- (4*n-1) = 0.at n=20A292476Maximal coefficient of (1 + x) * (1 + x^3) * (1 + x^5) * ... * (1 + x^(2*n-1)).at n=40A350504Number of solutions to +- 1 +- 3 +- 5 +- 7 +- ... +- (2*n-1) = 0 or 1.at n=40A367087