def af_to_genotypes(alt_af):
    """
    Returns the Hardy Weinberg equilibrium for a given alternate pooled allele frequency

    :param alt_af: [0, 1]
    :return: [homozygous Reference, heterozygous, homozygous Alternate]
    """
    return (1 - alt_af) ** 2, 2 * alt_af * (1 - alt_af), alt_af ** 2
