Don't forget that Rachmaninoff was a protege of Liszt. Tausig too, I believe.
Rachmaninoff only indirectly via Siloti or Zverev. I can't remember which one.
It should be noted that most of Liszt's pupils weren't traditional students. Many had met Liszt in somewhat of a masterclass setting, which he gave for free (or was it that he gave all lessons for free?).