At 10:30 AM 1999/03/02 -0500, Paul Derbyshire <[EMAIL PROTECTED]> wrote:
>At 12:07 AM 3/1/99 -0800, you wrote:
>>At 11:17 PM 2/28/99 -0800, Spike Jones wrote:
>>>It would not surprise me at all if instead of a list of primes, they
>>>send us the series 2,3,5,7,13,19,31,61,89,107,127,521...
>>
>>or 2, 3, 5, 7, 13, 17, 19, 31, 67, 127, 257 perhaps?
>
>This one doesn't even ring a bell. The same Mersenne primes in it though,
>and also some Fermat primes. (3, 5, 17, 257).
The first list, p=2,3,5,7,13,19,31,61,89,107,127,521,...
is the list of exponents which generate Mersenne primes, as in Mp= 2^p - 1
The second list, p=2,3,5,7,13,17,19,31,67,127,257
is the list of exponents Marin Mersenne thought generated Mersenne primes.
He was mostly right, but both included exponents that generate composites,
and excluded exponents that generate primes.
Stating the exponents rather than the base10 representation seems to
me to be almost the ultimate in data compression. (2^521-1 has 157 digits;
the advantage increases along with the exponent, uh, exponentially.)
Ken
________________________________________________________________
Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
