def index_color_node(i, c):
    """

    Given an index in the sequence, and a color, get the name of node who's index is i and color is c.

    :param i: Index in the sequence.
    :param c: Color, between 0 and 9.
    :return: Name of node corresponding to this index in s_star.

    **Example:** ::

      index_color_node(0, 9) = 'i_0_c_9'


    """
    return 'i_{}_c_{}'.format(i, c)