a=RandomInteger[{1,20}], b=RandomInteger[{1,20}], Table[F_(x-2) a+F_(x-1) b, {x, 1, 10}]

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.