> From: "Gary Untermeyer" <[EMAIL PROTECTED]>

> Greetings,

> Although this is not a question regarding mersenne primes, I thought I'd
> throw this out to the readers here.
 
> Let x be a prime number.  Consider the series of  numbers that take the
> following form:
 
> x,  x + n,  x + 2n,  x + 3n,  x + 4n,  x + 5n,  x + 6n,  where n is an
> even positive whole number.
 
> In this series of seven numbers, can anyone tell me why, if ALL of these
> numbers are prime, that the minimum value of n is 210 if all the terms
> are _consecutive_ prime numbers?

    The _consecutive_ hypothesis is not required, 
other than requiring x > 7 and n > 0.  If n is not divisible by 7,
then one of the seven numbers x, x + n, ..., x + 6n
will be divisible by 7, hence not prime.
[No two of the seven will be congruent modulo 7,
so all possible remainders modulo 7 must be represented.]
Likewise n must be divisible by 2, 3, 5.


    


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