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Iran Team Selection Test
2022 Iran Team Selection Test
5
5
Part of
2022 Iran Team Selection Test
Problems
(1)
Iran TST P5
Source: Iranian TST 2022 problem 5
4/2/2022
Find all
C
∈
R
C\in \mathbb{R}
C
∈
R
such that every sequence of integers
{
a
n
}
n
=
1
∞
\{a_n\}_{n=1}^{\infty}
{
a
n
}
n
=
1
∞
which is bounded from below and for all
n
≥
2
n\geq 2
n
≥
2
satisfy
0
≤
a
n
−
1
+
C
a
n
+
a
n
+
1
<
1
0\leq a_{n-1}+Ca_n+a_{n+1}<1
0
≤
a
n
−
1
+
C
a
n
+
a
n
+
1
<
1
is periodic.Proposed by Navid Safaei
Sequences
algebra