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Special primes (Posted on 2012-02-12) Difficulty: 3 of 5
There are two primes, both below 100, that evenly divide the sum of the primes less than themselves.

Find those two primes.

The only other such prime below 2,000,000 is M, the n-th prime.

Find M and n.

See The Solution Submitted by Ady TZIDON    
Rating: 5.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re: computer solution | Comment 2 of 3 |
(In reply to computer solution by Charlie)

A search for 369119 in Sloane's OEIS finds that the next such prime is 415074643, which is the 22096548th prime, and no others exist below 10^12.

BTW, Sloane does list 2 among these primes.

Edited on February 12, 2012, 6:36 pm
  Posted by Charlie on 2012-02-12 18:33:42

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