{{1,0,0,0,0}, {1,1,0,0,0}, {0,1,1,0,0}, {0,0,0,1,0},{0,0,0,1,1}}

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.