def METHOD_NAME(arr, seq):
    """Find a sequence in an array and return its index."""
    indexes = np.where(np.isclose(arr, seq[0]))
    for index in np.nditer(indexes[0]):
        if index % 3 == 0:
            if np.allclose(arr[index + 1], seq[1]) and np.allclose(arr[index + 2], seq[2]):
                return index
    return -1