def zernike_to_ansi(n, m):
    """Get the ANSI index for a pair of Zernike indices.

	Parameters
	----------
	n : int
		The radial Zernike order.
	m : int
		The azimuthal Zernike order.

	Returns
	-------
	int
		The ANSI index.
	"""
    return (m + n * n) // 2 + n
