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Prime Numbers

This tag is associated with 31 posts

By Mike Molony ⋅ August 26, 2014 ⋅ One comment

Find the 2000th hexagonal tile in which the differences between it and its 6 neighbors yield 3 primes.

By Mike Molony ⋅ July 15, 2014 ⋅ Post a comment

The prime factorisation of binomial coefficients

By Mike Molony ⋅ April 20, 2009 ⋅ 2 comments

Find the sum of the distinct square-free numbers in the first 51 rows of Pascal’s triangle.

By Mike Molony ⋅ December 19, 2012 ⋅ Post a comment

Find fractions that cannot be cancelled down (resilient fraction).

By Mike Molony ⋅ December 19, 2012 ⋅ Post a comment

Prime Subset Sums

By Mike Molony ⋅ March 22, 2015 ⋅ 3 comments

Find the number of factors in an enormous factorial.

By Mike Molony ⋅ June 15, 2009 ⋅ 2 comments

Investigating minimal repunits that divide by n.

By Mike Molony ⋅ June 15, 2009 ⋅ Post a comment

Finding composite values, n, for which n−1 is divisible by the length of the smallest repunits that divide it.

By Mike Molony ⋅ June 15, 2009 ⋅ Post a comment

Determining the first forty prime factors of a very large repunit.

By Mike Molony ⋅ June 16, 2009 ⋅ 4 comments

Investigating which primes will never divide a repunit containing 10**n digits.

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