Dreamshire

By Mike Molony ⋅ May 18, 2009 ⋅ 5 comments

Find the smallest number divisible by each of the numbers 1 to 20.

By Mike Molony ⋅ April 8, 2009 ⋅ 3 comments

How many circular primes are there below one million?

By Mike Molony ⋅ April 23, 2009 ⋅ 10 comments

Find the sum of all eleven primes that are truncatable from both left to right and right to left.

By Mike Molony ⋅ March 26, 2009 ⋅ 2 comments

Find the largest n-digit pandigital prime that exists

By Mike Molony ⋅ May 28, 2009 ⋅ 4 comments

Find the smallest odd composite that cannot be written as the sum of a prime and twice a square.

By Mike Molony ⋅ June 5, 2009 ⋅ 2 comments

Find arithmetic sequences, made of prime terms, whose four digits are permutations of each other.

By Mike Molony ⋅ April 12, 2009 ⋅ 5 comments

Find the prime number, below one-million, that can be written as the sum of the most consecutive primes.

By Mike Molony ⋅ May 27, 2009 ⋅ 16 comments

Find the smallest prime which, by replacing part of the number with the same digit, is part of an eight prime value set.

By Mike Molony ⋅ July 16, 2011 ⋅ 2 comments

Investigating numbers that can be expressed as the sum of a prime square, cube, and fourth power.

By Mike Molony ⋅ March 25, 2009 ⋅ 2 comments

Find the last ten digits of the non-Mersenne prime: 28433 × 2^7830457 + 1.

Prime Numbers