def get_dot_indices(face_index_from_1):
    """Get indices (from 0 through 20) corresponding to dots on the given face (from 1 through 6)."""
    if face_index_from_1 == 1:
        return [0]
    elif face_index_from_1 == 2:
        return [1,2]
    elif face_index_from_1 == 3:
        return [3,4,5]
    elif face_index_from_1 == 4:
        return [6,7,8,9]
    elif face_index_from_1 == 5:
        return [10,11,12,13,14]
    elif face_index_from_1 == 6:
        return [15,16,17,18,19,20]
    else:
        return []