MathDB
TOT 017 1982 Spring J3 S3 100 members with a_k > k

Source:

August 17, 2019
Sequenceinequalitiescombinatoricsalgebra

Problem Statement

a) Prove that in an infinite sequence ak{a_k} of integers, pairwise distinct and each member greater than 11, one can find 100100 members for which ak>ka_k > k.
b) Prove that in an infinite sequence ak{a_k} of integers, pairwise distinct and each member greater than 11 there are infinitely many such numbers aka_k such that ak>ka_k > k.
(A Andjans, Riga)
PS. (a) for juniors (b) for seniors