primes less than n and relatively prime to n

[Joshua Zucker]

On 1/19/07, Artur <grafix at csl.pl> wrote:
> 3 another definition of sequences look that same sequences. Any comment ?
> ARTUR
>
> A045572 Odd but not divisible by 5.

This sequence is infinite.

> A085820 Possible two-digit endings of primes (with leading zeros).

This is a finite sequence which contains the first few terms of A045572.

> A...... primes less than n and relatively prime to n
> {3, 7, 9, 11, 13, 17, 19, 21, 23, 27, 29, 31, 33, 37, 39, 41, 43, 47, 49,
> 51,
> 53, 57, 59, 61, 63, 67, 69, 71, 73, 77, 79, 81, 83, 87, 89, 91, 93, 97, 99}

I don't speak Mathematica but this looks a little weird.  There
certainly aren't 3 primes less than 1 and relatively prime to 1.  So
please clarify the definition for me, or explain what the Mathematica
code is doing?

Thanks,
--Joshua