Problems & Puzzles:
Puzzles
Puzzle
550.-
Consecutive
primes producing semiprimes
JM Bergot sent the following nice puzzle.
5*7 + 11*13 = 178 = 2*89 (√)
7*11 + 13*17 = 298 = 2*149 (√)
11*13 + 17*19 = 466 = 2*233 (√)
13*17 + 19*23 = 658 = 2*7*47 (X)
Q. Find a longer run of consecutive
primes adding this way to semiprimes?

Contributions came from Jan van Delden, Antoine Verroken,
Emmanuel Vantieghem
***
Jan, Antoine & Emmanuel wrote:
The first occurrence of a
sequence of 4 semiprimes starts with prime 17017471.
Jan added:
The next occurrence of 4 semiprimes starts
with prime 757658339.
***
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