Baudhayana sutras
The Baudhayana sūtras are a group of Vedic Sanskrit texts which cover dharma, daily ritual, mathematics, etc. They belong to the Taittiriya branch of the Krishna Yajurveda school and are among the earliest texts of the sutra genre, perhaps compiled in the 8th to 7th centuries BCE.
The Baudhayana sūtras consist of six texts:
the Śrautasûtra, probably in 19 Praśnas (questions),
the Karmāntasûtra in 20 Adhyāyas (chapters),
the Dvaidhasûtra in 4 Praśnas,
the Grihyasutra in 4 Praśnas,
the Dharmasûtra in 4 Praśnas and
the Śulbasûtra in 3 Adhyāyas.
The Baudhāyana Śulbasûtra is noted for containing several early mathematical results, including an approximation of the square root of 2 and the statement of a version of the Pythagorean theorem.
Baudhāyana Shrautasūtra
His shrauta sūtras related to performing Vedic sacrifices has followers in some Smārta brāhmaṇas (Iyers) and some Iyengars of Tamil Nadu, Yajurvedis or Namboothiris of Kerala, Gurukkal Brahmins, among others. The followers of this sūtra follow a different method and do 24 Tila-tarpaṇa, as Lord Krishna had done tarpaṇa on the day before amāvāsyā; they call themselves Baudhāyana Amavasya.