I got the Dragon Seekers quest with Farkas & travelled to Mount Anthor to kill the dragon, only there wasn't one there. I fast travelled to Silent Cave first, then to the Shrine of Azura, ran back and forth all over the mountain side & shouted several times to get attention, in general made a fool of myself and no dragon.... The really strange thing was the quest marker kept moving around on the main map but did not appear on the compass bar. The map also showed Mount Anthor cleared though I hadn't actually discovered it yet.... This in on pc with the patch and previously on xbox 360.