Help me prove/disprove this trig conjecture

[...snip...]
>Humans have a way of proclaiming brilliant discoveries that were, in
>fact, still partly unmade! 

Check out my blogs at dsprelated (dot) com for some brilliant discoveries.
 I've got more coming.  Click on "Cedron Dawg" in red to get to all four
of them.

In particular, for this problem, look at my blog article titled "DFT Bin
Value Formulas for Pure Real Tones".  Equations (12) through (17) do this
proof in the general case.

[...snip...]

>Rewrite phi as 2 pi phi 

It is good practice to rename the variable if you are going to do
something like this and call it a substitution.

[...snip...]
>
>The sum is NOT 0 if n = 1.

Dude, nice punch line except if n = 1 it is not a sum.  Otherwise, spot
on.

Ced
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