it means its XC2 , the binomial coefficient. X choose 2 = X*(X-1)/2 On 5/9/07, Bin Chen <[EMAIL PROTECTED]> wrote: > > > I also CC to comp.theory. > > On 5月9日, 下午4时27分, Bin Chen <[EMAIL PROTECTED]> wrote: > > (x) > > (2) > > > > with the upper and lower parenthesis concatenated to a big > > parenthesis, what math does this notation mean? I think there may have > > two, one is 2^x, another is "select 2 elements from x, with the order, > > how many combination the selection has". > > > > Which one is common? > > > > Thanks. > > Bin > > > > >
--~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algogeeks@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/algogeeks -~----------~----~----~----~------~----~------~--~---
