The Cunningham Project seeks to factor the numbers b^n +- 1 for b = 2, 3, 5, 6, 7, 10, 11, 12, up to high powers n. The Cunningham tables are the tables in the book *"Factorizations of b^n +- 1, b = 2, 3, 5, 6, 7, 10, 11, 12 up to high powers,*" by John Brillhart, D. H. Lehmer, J. L. Selfridge, Bryant Tuckerman, and S. S. Wagstaff, Jr., American Mathematical Society, Providence, Rhode Island, third edition, 2002. Although the first two editions were published as paper books, the third edition is an electronic book available at http://www.ams.org/books/conm/022/ . On Mon, Sep 25, 2017 at 9:27 PM, Marc LeBrun <mlb@well.com> wrote:
On Sep 25, 2017, at 5:30 PM, James Davis <lorentztrans@gmail.com> wrote:
Thanks! That saves me a week.
Then perhaps I can waste you some more time?
So square-free, the exceptions pop out! By eyeball it seems like 11^2 is a divisor when n = an odd multiple of 11.
And 7^2 divides n=21 and 63, and there's even a 13^2 for n=39 (no doubt all these are related to n=3 being 7 11 13?)
What is the smallest n divisible by a cube? By two distinct squares? By any square that's relatively prime to 1001?
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