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Baltic Way
1997 Baltic Way
10
10
Part of
1997 Baltic Way
Problems
(1)
13|S(n) for some n among 79 consecutive integers
Source: Baltic Way 1997
1/28/2011
Prove that in every sequence of
79
79
79
consecutive positive integers written in the decimal system, there is a positive integer whose sum of digits is divisible by
13
13
13
.
number theory proposed
number theory