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23
2n digit number such that a_{2n} ... a_1 = (a_n ... a_1)^2
2n digit number such that a_{2n} ... a_1 = (a_n ... a_1)^2
Source:
December 6, 2010
number theory unsolved
number theory
Problem Statement
Does there exist a
2
n
2n
2
n
-digit number
a
2
n
a
2
n
−
1
⋯
a
1
‾
\overline{a_{2n}a_{2n-1}\cdots a_1}
a
2
n
a
2
n
−
1
⋯
a
1
(for an arbitrary
n
n
n
) for which the following equality holds:
a
2
n
⋯
a
1
‾
=
(
a
n
⋯
a
1
‾
)
2
?
\overline{a_{2n}\cdots a_1}= (\overline{a_n \cdots a_1})^2?
a
2
n
⋯
a
1
=
(
a
n
⋯
a
1
)
2
?
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