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2015 Cono Sur Olympiad
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2015 Cono Sur Olympiad
Problems
(1)
Divisibility by 81 (2015 OMCS #1)
Source:
5/16/2015
Show that, for any integer
n
n
n
, the number
n
3
ā
9
n
+
27
n^3 - 9n + 27
n
3
ā
9
n
+
27
is not divisible by
81
81
81
.
Divisibility
number theory