2025 SSMO Relay Round 4 Problems
Problem 1
Call a positive integer chuzzed if the sum of the digits in its binary representation is equal to the units digit of its base- representation. Similarly, call a positive integer chopped if its binary representation does not contain two consecutive ones. Find the number of positive integers less than
that are chuzzed and chopped.
Problem 2
Let Jonathan and Kate are playing a game with
sticks. On each turn, a player may remove
or
sticks. The player who picks up the last stick loses. Kate is first to remove sticks, and both players play optimally. For how many values of
in the range
does Kate have a winning strategy?
Problem 3
Let A particle moves in the coordinate plane such that at any time
its position is
Over the time interval
the particle lies on at least one coordinate axes
times. If the minimal value of
can be written as
for relatively prime positive integers
and
find
.