Let's work that through Doug. 40 fish, throw one away. That's 39. 13 each, so early riser goes off with his share. That leaves 26. Throw one of those away and 25 are left, which doesn't divide evenly by 3.

79 fish works though. Thow one away = 78. Take 26, leaving 52. Next chap throws one away, leaving 51. He takes his 17, leaving 34. Lazybones throws 1 away and takes his 11, leaving 22 to rot.

Dirac's answer was much better, though I think he cheated a bit. He proposed that the number of fish caught was -2. Throw one away, that's -3. Take your third, and that leaves -2 again. Any number of fishermen could have shared the catch in this manner.