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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.



