Select[Range[100], Mod[#, 3] == 0 Or Mod[#, 5] == 0 Or Mod[#, 8] == 0 &]

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.