Y by
Fix a nonnegative integer
to define a sequence of integers
by letting
be the smallest integer (strictly) greater than
making
into a perfect square. Let
be the set of positive integers not expressible as the difference of two terms of the sequence
Prove that
is finite and determine its size in terms of 









This post has been edited 2 times. Last edited by oVlad, May 14, 2023, 10:18 AM