IMO Shortlist 1992 problem 17
Kvaliteta:
Avg: 0,0Težina:
Avg: 0,0 Let be the number of digits equal to one in the binary representation of a positive integer . Prove that:
(a) the inequality holds;
(b) the above inequality is an equality for infinitely many positive integers, and
(c) there exists a sequence such that
goes to zero as goes to .
Alternative problem: Prove that there exists a sequence a sequence such that
(d) ;
(e) an arbitrary real number ;
(f) an arbitrary real number ;
as goes to .
(a) the inequality holds;
(b) the above inequality is an equality for infinitely many positive integers, and
(c) there exists a sequence such that
goes to zero as goes to .
Alternative problem: Prove that there exists a sequence a sequence such that
(d) ;
(e) an arbitrary real number ;
(f) an arbitrary real number ;
as goes to .
Izvor: Međunarodna matematička olimpijada, shortlist 1992