"""Converts a Julian Day Number (JDN) to a Gregorian date.

The function uses a series of mathematical transformations to convert the given Julian Day Number
into a Gregorian date, which is returned as a `date` object from the `datetime` module.

Args:
    jdn (int): The Julian Day Number to be converted. Must be a non-negative integer.

Returns:
    date: A `date` object representing the Gregorian date corresponding to the given JDN.
"""