Y by dangerousliri, R8kt, MuhammadAmmar, SatisfiedMagma
For a positive integer
, let
be all positive integers smaller than
that are coprime to
. Find all
such that
for all 
Here
is the largest positive integer that divides both
and
. Integers
and
are coprime if
.
Proposed by Paulius Aleknavičius, Lithuania







Here






Proposed by Paulius Aleknavičius, Lithuania
This post has been edited 3 times. Last edited by EeEeRUT, May 11, 2025, 11:49 AM