c++ array. Looking for better solution
You're almost there, you just need to use std::pow() to raise a value to an arbitrary power, and add another for-loop to handle the repetetive work of filling in all the remaining columns:
for(int i = 0; i &lt; A.size(); i++)
{
     A[i][0] = 2.0 + 0.1 * i;
     A[i][1] = 1 / A[i][0];

     for(int j = 2; j &lt; A[i].size(); j++)
     {
         A[i][j] = std::pow(A[i][0], j);
     }
     ...
}