67109125
domain: N
Appears in sequences
- a(n) = Sum_{ k, k|n } 2^(k-1).at n=26A034729
- a(n) = (-1)^(n+1) * coefficient of x^n in Sum_{k>=1} x^k/(1+2*x^k).at n=26A081295
- Numbers whose binary indices are all powers of 3, where a binary index of n (row n of A048793) is any position of a 1 in its reversed binary expansion.at n=15A368531
- a(n) = Sum_{d|n} (-1)^(d-1) * 2^(n/d-1).at n=26A373275