69750domain: NAppears in sequencesa(n) = T(2*n, n-2), where T is given by A026519.at n=8A026527Duplicate of A026527.at n=8A026544Partial sums of floor(5^n/7).at n=7A178711Numbers k such that k and uphi(k) have the same set of prime divisors, where uphi is the unitary totient function (A047994).at n=32A329859