« Vrati se
Denote by d(n) the number of divisors of the positive integer n. A positive integer n is called highly divisible if d(n) > d(m) for all positive integers m < n.
Two highly divisible integers m and n with m < n are called consecutive if there exists no highly divisible integer s satisfying m < s < n.

(a) Show that there are only finitely many pairs of consecutive highly divisible
integers of the form (a, b) with a\mid b.

(b) Show that for every prime number p there exist infinitely many positive highly divisible integers r such that pr is also highly divisible.

Slični zadaci

#NaslovOznakeRj.KvalitetaTežina
2199IMO Shortlist 2005 problem N313
2200IMO Shortlist 2005 problem N413
2202IMO Shortlist 2005 problem N614
2203IMO Shortlist 2005 problem N72
2232IMO Shortlist 2006 problem N60
2318IMO Shortlist 2009 problem N61