3 problems
Let be the least exponent such that, for some , every interval of the form … contains an integer , where … and all four integers lie in … an…
Ruzsa's conjecture. There is a constant such that, for every positive integer , the number of such divisors is at most .
Erdős–Rosenfeld conjecture. There is an absolute constant such that, for every , the number of such divisors is at most whenever .