## 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

**Unique-IP document downloads:** 168 times

**Add your own feedback and questions here:**

*You are equally welcome to be positive or negative about any paper but please be polite. If you are being critical you must mention at least one specific error, otherwise your comment will be deleted as unhelpful.*

*
*