> Those with some math will know that e=exp(1) is transcendental.
> This was proved by Hermite in 1873.  From that it is trivial
> that exp(0.1) is also transcendental.  Therefore no linear
> combination (with integer coefficients) of exp(0.1), exp(0.2),
> ..., exp(3.0) can be 0 except the trivial one.
> 

Maybe I didn't say what I meant. I was not suggesting using powers of e.
I meant something simpler. Let's say your alphabet is just {a,b} Then the
map
based on the array [1,m+1] and using  key += array[s] 
will correctly identify anagrams for strings of a and b which have length 
no greater than m.

> This allows us to come up with a hashing function using floating
> point numbers.  The only issue is what point we will get into
> pain from round-off errors.
> 
As soon as I have time, I thought of checking my "slide rule" version the
brute force way,
to see when it breaks.

Barry