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4
K 4
K 4
Source:
May 25, 2007
function
induction
algebra
polynomial
functional equation
complex numbers
Functional Equations
Problem Statement
Find all functions
f
:
N
→
N
f: \mathbb{N}\to \mathbb{N}
f
:
N
→
N
such that for all
n
∈
N
n\in \mathbb{N}
n
∈
N
:
f
(
f
(
f
(
n
)
)
)
+
f
(
f
(
n
)
)
+
f
(
n
)
=
3
n
.
f(f(f(n)))+f(f(n))+f(n)=3n.
f
(
f
(
f
(
n
)))
+
f
(
f
(
n
))
+
f
(
n
)
=
3
n
.
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