Matrix with gradually increasing!

Hi everyone! Can somebody help me to write a code to return a matrix with the following form: [1 1 1 1 1;1 1 1 1 0;1 1 1 0 0;1 1 0 0 0;1 0 0 0 0]? it's 5x5 square matrix Thanks in advance

Answer 1

[John D'Errico]

flip(tril(ones(5)))
ans =
     1     1     1     1     1
     1     1     1     1     0
     1     1     1     0     0
     1     1     0     0     0
     1     0     0     0     0

[Omar]

You're awesome :) Thanks a lot