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Kosovo Team Selection Test
2017 Kosovo Team Selection Test
2
2
Part of
2017 Kosovo Team Selection Test
Problems
(1)
2017 Kosovo TST Problem 2
Source:
3/19/2017
Prove that there doesn't exist any function
f
:
N
→
N
f:\mathbb{N}\rightarrow \mathbb{N}
f
:
N
→
N
such that :
f
(
f
(
n
−
1
)
=
f
(
n
+
1
)
−
f
(
n
)
f(f(n-1)=f(n+1)-f(n)
f
(
f
(
n
−
1
)
=
f
(
n
+
1
)
−
f
(
n
)
, for every natural
n
≥
2
n\geq2
n
≥
2
function
algebra