## A Fifth Smarandache Friendly Prime Pair

**Authors:** Philip Gibbs

A Smarandache friendly prime pair (SFPP) is a pair of prime numbers (p,q), p < q, such that
the product pq is equal to the sum of all primes from p to q inclusive. Previously four such
pairs were known: (2,5), (3,13), (5,31) and (7,53). Now a fifth one is found by a brute force
computer search. A heuristic approximation can be to estimate the expected number of SFPPs in
a given interval. The result suggests that the probability of further pairs existing is about 0.07.

**Comments:** 4 pages

**Download:** **PDF**

### Submission history

[v1] 28 Apr 2010

[v2] 30 Apr 2010

[v3] 2 May 2010

[v4] 4 May 2010

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