def death_delta(state, mu):
    """
    Calculates the sum of all death rates for ``state``.

    Parameters
    ----------
    state : list[int]
        Number of cells per clonotype.
    mu : float
        Single cell death rate.

    Returns
    -------
    delta_value : float
        Sum of all death rates for state.
    """

    delta_value = 0.0

    for i in range(len(state)):
        delta_value += state[i] * mu

    return delta_value