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Topic: Two flavors of Prime Numbers involved in their running sums
Replies: 4   Last Post: Jan 24, 2011 6:13 AM

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 Henry Posts: 1,089 Registered: 12/6/04
Re: Two flavors of Prime Numbers involved in their running sums
Posted: Jan 21, 2011 4:45 AM

On Jan 20, 2:28 pm, rom...@sbcglobal.net wrote:

> For example,  all the 41542 PN's up to and including 500501
> sum to 9.935243881e9  which is also a PN.

No.

The 41542 nd prime number is 500057 and the running sum is 9916236331
= 937 * 2141* 4943

The 41580 th prime number is 500501 and the running sum is 9935247137
= 43 * 231052259

> And all the 63392 PN's up to and including 792919 sum to
> 2.4050718917e+10 which is also a PN

Also wrong. Try http://oeis.org/A013917 and http://oeis.org/A013917/b013917.txt
for prime numbers where the running sum is also prime. The list
includes 500249 and 500729, and also 792731 amd 793139.

Date Subject Author
1/20/11 rom126@sbcglobal.net
1/20/11 Dork Spotter
1/21/11 Henry
1/21/11 rom126@sbcglobal.net
1/24/11 Henry