Provia 100F is a very stable film, so testing is a little tricky. From all the measured data I've been able to find, the best fit for it's reciprocity characteristics is as follows:
y = 0.9727x + 7.629E-7x^3
The E means it is *10^-7 which makes it very small... 0.0000007629 to be precise. Sorry bout that! It's what happens when a film has very very little reciprocity failure.