On Dec 10, 2007 1:42 PM, Brian Schott <[EMAIL PROTECTED]> wrote: > Having no idea where to start on this one, I have > been looking for other smaller 61's to investigate. Can > someone verify that 7 and 13 are, but 5 and 11 are not, > other 61s?
The only way i know of for 61 to take on different values is to use different numeric bases. This essentially turns 61 into the expression 1+6*y. For example, 100b61 601 Of course, these are not "61" in any usual sense of the word, As for other values where the mechanism behind this problem can be relevantly applied, I believe any value greater than 2 can be used. (2 can not be used because everything is divisible by 1, and you do not have any other options to eliminate.) Anyways, here's the answers I get for the numbers you mentioned: allbut2 5 7 11 13 10 252 712800 111196800 And, I do not think I left any bugs in there: allbut2=:3 :0"0 n=.1+i.y p=.n e. i.&.(p:inv) y s=.last (adj p)*.+./"1(> 1 >./\. ])_ q:n */x:n^-.s +. last p *.adj s ) where adj=:[: +./ 1 _1 |.!.0"0 1 ] last=:</\&.|. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
