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Hello fellow hobby factorizer :)

I wanted to share this small gem of a paper in case it helps you like it's helped me:

"Simple divisibility rules for the 1st 1000 prime numbers": https://arxiv.org/pdf/math/0001012

Meh, most of those aren’t all that helpful. Multiplying the last digit by -17 and adding that to the rest of the number to do a divisibility test for 19? I’d be more inclined to do the right-side reduction which isn’t appreciably different and, if you’re good at keeping some side numbers in working memory can give you the actual quotient if it is divisible which these rules won’t give you.

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