A neater (imo) way of writing that formula is
x = ((2 ^ n) - 1)(2 ^ (n - 1))
But that is only going to hit the even perfect numbers. There still might be odd perfect numbers out there. Nobody knows. Brute force checking has shown there are no odd perfect numbers that fit in 64 bits. But relying on this previously-done brute force checking would be just as bad as writing the known perfect numbers out directly in code, no? ;-)
this is a thing i don't get. they say euler has shown that the rule is valable for any perfect, respectively marsenne. and yet they say there might be even perfects... can anyone throw a light upon this?
EDIT: oh, and about the minimum size of that odd number, by the time i write this, it has more than 300 digits.
Last edited by moonlord; 08-21-2005 at 07:53 AM.
Two strings walk into a bar. The first one says, 'Bartender! Bartender! I want a drink!'. The second one says, 'Bartender! Bartender! I want a drink too! Blaaaaaaaaah eeeeeeeek yaaaaaaak oooooooh'. The first one says, 'Please excuse my friend. He isn't null term--'.
Um, all known perfect numbers are even. Euler's proof applies to all even perfect numbers.they say euler has shown that the rule is valable for any perfect, respectively marsenne. and yet they say there might be even perfects... can anyone throw a light upon this?
Look up a C++ Reference and learn How To Ask Questions The Smart WayOriginally Posted by Bjarne Stroustrup (2000-10-14)
oh, sorry, i always confuse these. so, even is when x%2==0 and odd when x%2==1? then you must read my post the other way
Two strings walk into a bar. The first one says, 'Bartender! Bartender! I want a drink!'. The second one says, 'Bartender! Bartender! I want a drink too! Blaaaaaaaaah eeeeeeeek yaaaaaaak oooooooh'. The first one says, 'Please excuse my friend. He isn't null term--'.
