Max wrote: >> (ii) n = 3*A028982(m) for all m>=1. >> Note that A028982 lists positive integers having an odd sum of divisors. > The conjecture is true except that (ii) should be > (ii) n = 3^s*A028982(m) for all m>=1 and _odd_ s>=1. Oh. They are actually equivalent. Because if m is in A028982 then 9m is also in A028982. Max