Sierpiński number base 5

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A Sierpiński number base 5 is a value of k such that k × 5n + 1 is always composite.

Using the same method presented in the Sierpiński problem article, it was found that 159,986 × 5n + 1 is multiple of 3, 7, 13, 31 or 601 (the covering set) depending on the value of n, so it is always composite.

In order to demonstrate whether 159,986 is the smallest Sierpiński number base 5 or not, a distributed computing project was created named Sierpiński-Riesel Base 5