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2023-IMOC
A1
A1
Part of
2023-IMOC
Problems
(1)
Iterative FE
Source: IMOC 2023 A1
9/9/2023
Find all functions
f
:
N
→
N
f:\mathbb{N} \rightarrow \mathbb{N}
f
:
N
→
N
such that for all positive integers
n
n
n
, there exists an unique positive integer
k
k
k
, satisfying
f
k
(
n
)
≤
n
+
k
+
1
f^k(n)\leq n+k+1
f
k
(
n
)
≤
n
+
k
+
1
.
algebra