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Argentina Contests
Argentina National Olympiad
2013 Argentina National Olympiad
5
5
Part of
2013 Argentina National Olympiad
Problems
(1)
last numbers on board from 1-2013
Source: 2013 Argentina OMA Finals L3 p5
1/15/2023
Given several nonnegative integers (repetitions allowed), the allowed operation is to choose a positive integer
a
a
a
and replace each number
b
b
b
greater than or equal to
a
a
a
by
b
ā
a
b-a
b
ā
a
(the numbers
a
a
a
, if any, are replaced by
0
0
0
). Initially, the integers from
1
1
1
are written on the blackboard until
2013
2013
2013
inclusive. After a few operations the numbers on the board have a sum equal to
10
10
10
. Determine what the numbers that remained on the board could be. Find all the possibilities.
combinatorics
algebra