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As an exercise to the for the reader show that any pair of twin primes surrounds a multiple of 6.


Not quite true: the first twin primes, 3 and 5, surround 4, not divisible by 6. However, for any other twin primes, both will not have factors of 2 or 3, so the number between them must have a factor of 2 and a factor of 3 (the latter by the same logic as in the parent post: otherwise three numbers in a row would not have a factor of 3).


Arghh. True.


Any pair of consecutive odds both of which are not divisible by 3 surround a multiple of 3


5 and 7?


those surround 6.




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