There are a couple freeware score writers one can download, TuxGuitar and MuseScore. MuseScore's web site has a fairly large library of scores one can download. I've used both in the past but each lacked a feature I thought important to me. So far GP6 has done everything I've asked of it. Perhaps the nicest feature is that one can select from a long list of instruments to play back a score, supposedly the acoustic piano is a Steinway. One can download a free trial version of GP6, it is limited in some way but I can't remember if it is that it won't let you save a file or it is that it won't let you print a score, or both.
I've been using GP6 for about year, mostly creating exercises for guitar to address specific technical issues, or when working with some book that doesn't like being on a music stand then I create the sheet music just for the sake of convenience. I also spend some time working on classical guitar and there is tendency for exercises to show up as duets so it is handy to have one part or the other being played by the score writer to play along with. For piano something new has happened, I've a three ring binder now with my repertoire. At the moment this is limited (three songs, all now up to tempo, one melody only) but that there is anything at all three weeks after resuming piano is very pleasing. That this is new comes from my change in perception on the importance of having a repertoire with which one can practice the skills one learns from these courses.
Earlier I had noticed that this chord progression shows up again on p16 as a pedal exercise. I had just sat down to check if it appeared again later when I read your post. And so it does. Once to hear the contrast of the C being replaced with Am (p19), and again transposed to another key (p29). I wouldn't be at all surprised if it shows up a couple more times.
So one might expect that between the way I'm practicing it currently, the way it is on the CD, the contrast with Am version, and the transposed version that it is likely I'll prep sheet music for each and should I do so I'll add them to this thread unless someone beats me to it.
There is something familiar about this progression, I know it from somewhere, I might even have it on CD or vinyl, but I can't place it. I want to say Billy Joel but I'm just guessing.