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ITAMO
2016 ITAMO
4
4
Part of
2016 ITAMO
Problems
(1)
(a+1)^n+a-1 is a power of 2
Source: ITAMO 2016, Problem 4
5/11/2016
Determine all pairs of positive integers
(
a
,
n
)
(a,n)
(
a
,
n
)
with
a
≥
n
≥
2
a\ge n\ge 2
a
≥
n
≥
2
for which
(
a
+
1
)
n
+
a
−
1
(a+1)^n+a-1
(
a
+
1
)
n
+
a
−
1
is a power of
2
2
2
.
number theory