Tugadharma - Verse 15-16

The sin acquired by a Brahmin by prohibited association with the woman of a different caste, even during a iong time, disappears by reciting the Gdyatri mantra with pranava ten times and by prdnayama three hundred times. Even the sin of killing a Brahmin (disappears by such a practice), then should we say about the other (less grave) sins?