Give a regular expression for the smallest language L over 0

Give a regular expression for the smallest language L over {0,1} so that epsilon is not a subset of L, 0 is a subset of L, and for every x in L, for every w in Sigma*, wx is a subset of L and xw is a subset of L

Solution

Given that:

Sigma = {0,1}

L = {0,01,10,101,001,01001,010,.......}

So, the R.E = (0+1)*