40822

Appears in sequences

• a(n) = [x^n] Product_{k>=1} (1 + x^k)*(1 - x^(n*k))/((1 - x^k)*(1 + x^(n*k))).at n=26A304627
• Expansion of Product_{k>=1} 1/(1 - (k - 1)*x^k).at n=23A319110