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Some prime sequences (Posted on 2018-07-04) Difficulty: 3 of 5
What numbers N are the sum of a sequence of consecutive primes such that the product of the first and last numbers in the sequence is N?

No Solution Yet Submitted by Ady TZIDON    
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re: The sequence | Comment 5 of 11 |
(In reply to The sequence by Jer)

By its nature, the solutions to this puzzle must be semiprimes, being the product of the first prime in the sequence and the last number (prime) in the sequence. The fourth number in each of these sequences is not a semiprime:


 2935561623745 = 5*19*53*61* 9557887
 10225245560 = 2*2*2*5*503*508213

I'm still trying to figure out the difference between these two sequences.

Edited on July 5, 2018, 7:48 pm
  Posted by Charlie on 2018-07-05 10:58:19

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