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2
K 2
K 2
Source:
May 25, 2007
function
induction
strong induction
number theory
prime factorization
Functional Equations
Problem Statement
Find all surjective functions
f
:
N
→
N
f: \mathbb{N}\to \mathbb{N}
f
:
N
→
N
such that for all
m
,
n
∈
N
m,n\in \mathbb{N}
m
,
n
∈
N
:
m
∣
n
⟺
f
(
m
)
∣
f
(
n
)
.
m \vert n \Longleftrightarrow f(m) \vert f(n).
m
∣
n
⟺
f
(
m
)
∣
f
(
n
)
.
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