Re: "Dr." Elphinstone
 

[quote="bragoria"]After being inspired by the mathematical research performed by 'Dr.' Elphinstone... ;) (http://www.mersenneforum.org/viewtopic.php?t=832) I'd thought I'd post the following puzzle...

Find a small factor (or any factor) of the Mersenne number 2^(157,456,128,945,769)-1.

btw - I haven't actually found a factor for this number... and it would take longer than the age of the universe to test this number for primality on a P4, so if you can't find a small factor, you should probably just give up.

But don't worry, it's only 47,399,017,813,816 digits long![/quote]

Since Richard Wackerbarth locked the original thread due to its being off-topic, I had to start a new one to reply:

M157456128945769 has a factor: 2391758598686231111.

I checked up to 72 bits - no other factors turned up in this range.

edit: quick fingers, slow brain. :surprised:ops:

It is [b]still[/b] off topic. Please do not post this kind of discussion under "Puzzles"