I noticed I forgot to include 3, it was only distraction.

However I think this statement is enaugh:

the set of prime numbers = 2, 3, 5 PLUS all odd numbers > 5, not ending by 5 and not composite.

7 is included: 7>5, 7 is odd not ending by 5 AND not composite.

9 is not included: 9 is composite (3^2)

11 is included: 11>5, 11 is odd not ending by 5 AND not composite.

By "composite number" I meant an integer that is the product of two or more integers. I hope I used

the right translation of what I meant.

Of course we can use a more concise statement:

pimes = all not composite numbers > 1.

We will find that, with the exception of 2 and 5, all prime numbers have as final digit one of

these: 1, 3, 7, 9.

----- Original Message -----

From: "Mary & Graeme" <candlesque@...>

To: "Mazzarello Gianni" <g.mazzarello@...>

Sent: Tuesday, December 07, 2004 12:32 AM

Subject: Re: [PrimeNumbers] another way to calculate primes

> May I make an observation here?

>> the set of prime numbers = 2, 5 PLUS all odd numbers > 5, not ending by

>> 5 and not composite.

> Might it not be more correct to state:

> the set of prime numbers = 2,3,5,7,11 PLUS all odd numbers > 5, not ending by

> 5 and not composite.

> ... since the first statement would seem to allow 9 as a prime, and omits 3?