Virgil
Posts:
6,993
Registered:
1/6/11


Re: A finite set of all naturals
Posted:
Aug 16, 2013 3:33 PM


In article <c10s09pu0gs0av09l4gfqrrpbdm5gj510n@4ax.com>, quasi <quasi@null.set> wrote:
> quasi wrote: > > > > Or how about the following instead? > > > > odd(x) <> [x*y=2*z] > Ew[y=2*w] > > to Nam: > > Since you've has already defined various versions of even(x), > my above definition of odd(x) can be expressed more simply as: > > odd(x) <> even(x*y) > even(y) > > Doesn't that qualify as a "positive formula"? > > quasi
I like that one! 

