Sorry, that link does not open up a lecture page.  But what you are calculating seems to be somewhat wrong.  Phase noise is a broadband noise. Phase noise is typically measured from 100 hz to 10 Mhz from the carrier, and the level at each frequency offset point varies.

So if you have a phase noise measourement, and want to turn it into rms jitter, you have to INTEGRATE it over the frequency limits of 100 Hz to 10 MHz, do a little more math, and then you have an answer.

Possibly the example you were looking at was not phase noise at all, but relating a discrete freuqency spurious sidband to the jitter that one tone would cause?

here is a spreadsheet "allan variance from phase noise" that might help your understanding:
http://www.wenzel.com/documents/spread1.htm

there are other spreadsheets out there for jitter to phase noise calculation

Rich
Maguffin Microwave