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2014 ASDAN Math Tournament
18
18
Part of
2014 ASDAN Math Tournament
Problems
(1)
2014 General #18
Source:
7/5/2022
A two-digit positive integer is
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<span class='latex-italic'>primeable</span>
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if one of its digits can be deleted to produce a prime number. A two-digit positive integer that is prime, yet not primeable, is
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<span class='latex-italic'>unripe</span>
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. Compute the total number of unripe integers.
2014
General Test