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Problem 8
f(f(n))+f(n)=2n
f(f(n))+f(n)=2n
Source:
September 14, 2014
function
induction
strong induction
algebra unsolved
algebra
Problem Statement
find all function such that
f
:
N
−
>
N
f:N->N
f
:
N
−
>
N
for every
n
∈
N
n\in\mathbb{N}
n
∈
N
,
f
(
f
(
n
)
)
+
f
(
n
)
=
2
n
f(f(n))+f(n)=2n
f
(
f
(
n
))
+
f
(
n
)
=
2
n
PLZ->(solution not to use characterastic equation)<-
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