def contiguous(l, start, end):
    """ checks that a list of integers are consequtive """
    if not l:
        return False
    if l[0] != start:
        return False
    if l[-1] != end:
        return False

    # for consequtiveness, look at the integers in pairs
    pairs = zip(l, l[1:])
    if not all([p[0]+1 == p[1] for p in pairs]):
        return False

    return True