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2000 JBMO ShortLists
4
4
Part of
2000 JBMO ShortLists
Problems
(1)
abcd to dcba - JBMO Shortlist
Source:
10/30/2010
Find all the integers written as
a
b
c
d
‾
\overline{abcd}
ab
c
d
in decimal representation and
d
c
b
a
‾
\overline{dcba}
d
c
ba
in base
7
7
7
.
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number theory