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1
Function on positive integers
Function on positive integers
Source: Moldova TST Problem 1
March 31, 2015
function
functional equation in N
algebra
Problem Statement
Find all functions
f
:
Z
+
→
Z
+
f : \mathbb{Z}_{+} \rightarrow \mathbb{Z}_{+}
f
:
Z
+
→
Z
+
that satisfy
f
(
m
f
(
n
)
)
=
n
+
f
(
2015
m
)
f(mf(n)) = n+f(2015m)
f
(
m
f
(
n
))
=
n
+
f
(
2015
m
)
for all
m
,
n
∈
Z
+
m,n \in \mathbb{Z}_{+}
m
,
n
∈
Z
+
.
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