Wikipedia says that 1 is no longer considered prime by mathematicians. How should it be handled for the purposes of this challenge?

Looking at the example output from "primesums.exe 1 29 6 sumsout.txt" one thing I do not see is:

sum(1:9) = 27 = 3**3

So my guess is that 1 is not prime. This leads to my next question...

Can we assume that the first and second command line arguments are prime?

- Rick