--- Marcel Martin <

znz@...> wrote:

>

> In short, the sequence is constituded of the gcd's

> (2^p_i-1,3^p_i-1).

The 'simple script' was:

$ calc

'p=1;while(p<999){p=nextprime(p);g=gcd(2^p-1,3^p-1);if(g>1)print g;}'

i.e. you're spot on.

Well done.

I'm reading mail in reverse, but s far you're the first to have

described it in the terms that I vieed it in. Which makes you a

winner, if there is such a thing. :-|

> As far as I am concerned, it is impossible to find such result.

> Each

> time I try to solve a puzzle, I believe that the key is to find

> _the_

> interesting property which justifies the puzzle :-)

>

> >Bonus question:

> >What comes next in this subsequence of the above?

> > 193949641, ...

>

> 4007,

Hmmm, those looked a little prime to me.

Anyone got any composites that are in the sequence?

Of course, if you obeyed orders, then the answer is p s.t. Order(2,

mod p) = Order(3, mod p). So a coincidence isn't impossible. One

composite was interesting, but I never found a second...

Phil

=====

--

"One cannot delete the Web browser from KDE without

losing the ability to manage files on the user's own

hard disk." - Prof. Stuart E Madnick, MIT.

So called "expert" witness for Microsoft. 2002/05/02

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