Fourier Series

Hey all,

I've been working on computing the fourier series of the problem I posted below. It shouldn't be difficult but I keep getting the incorrect answer. Take a look at it and tell me what you think.

The thing is I don't actually care about representing my signal as a fourier series, I just care about the cn frequency samples, I need an accurate representation of the frequency spectrum, and an FFT doesn't do the job I need.

However, if the fourier coefficients are correct, then my time domain fourier series should obviously be correct as well.

Thanks

Edit: I've done this problem at least 4 different times and I keep getting a different and incorrect answer.

5th time is the charm I suppose. I got the correct answer.

Here is the solution if anyone is interested.

Thanks anyway.