59271

Appears in sequences

• a(n) = number of numbers with digit sum n, not greater than the n-th repunit (cf. A052222).at n=10A242622
• Expansion of Product_{k>0} (1 + (2*k-1)*x^(2*k-1))/(1 - 2*k*x^(2*k)).at n=20A319859