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PEN M Problems
13
13
Part of
PEN M Problems
Problems
(1)
M 13
Source:
5/25/2007
The sequence
{
x
n
}
\{x_{n}\}
{
x
n
}
is defined by
x
0
∈
[
0
,
1
]
,
x
n
+
1
=
1
−
∣
1
−
2
x
n
∣
.
x_{0}\in [0, 1], \; x_{n+1}=1-\vert 1-2 x_{n}\vert.
x
0
∈
[
0
,
1
]
,
x
n
+
1
=
1
−
∣1
−
2
x
n
∣.
Prove that the sequence is periodic if and only if
x
0
x_{0}
x
0
is irrational.
function
induction
pigeonhole principle
calculus
integration
Recursive Sequences