Problem of the Week (24)

Problem of the Week

Problem of the Week (24)

Zach Marinov, 3 months ago 0 1 min read 32

Compute the least positive integer $n$ for which $10n+1$ and $10n+9$ are prime but $10n+3$ and $10n+7$ are composite.

Source: ARML Local 2020

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Zach Marinov

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