Inverse Powers
==============

Let's consider the inverse powers mathematical sequence of a given number :math:`n` which is defined as:

    .. math:: p_i = \frac{1}{n^i}, i \geq 0

Implement the following Python function in the :mod:`invpow` module (file :file:`invpow.py`):


    .. py:function:: invpow(n, eps)
    
        | *takes* ``n, eps`` :class:`float` numbers where ``n`` is any number and ``eps`` represents a tolerance
        | *returns* a :class:`float` with the sum of all those terms of this sequence until the difference between two consecutive terms is negligible under an epsilon tolerance, i.e. :math:`abs(t_i - t_{i+1}) < eps`.

For exemple:

   .. literalinclude:: invpow-test.txt
      :language: python3
      :start-after: --ini
      :end-before: --fi

Doctests are available at the :download:`invpow-test.txt <invpow-test.txt>` file.