27027000
domain: N
Appears in sequences
- a(n) = the smallest number k such that floor(Sum_{d|k} 1/tau(d)) = n.at n=29A265393
- Composite k for which lcm(k, phi(k)) + lcm(k, tau(k)) = lcm(k, sigma(k)).at n=28A328651
- El Gradechi's hybrid coefficients alpha^{4,6}_n.at n=24A331769
- Harmonic numbers (A001599) with a record harmonic mean of divisors.at n=22A335316
- Harmonic numbers (A001599) with a record number of divisors.at n=15A335317
- Harmonic numbers (A001599) k with a record abundancy index sigma(k)/k.at n=10A335318