Chandah-shastra: The Prastara — the Combinatorics of Meter

Verse 1 (garuda.1.212.1)

सूत उवाच । प्रस्तार आद्यगोऽथो लः परतुल्योऽथ पूर्वगः । नष्टमध्ये समेंऽके लः समेऽर्धे विषमे गुरुः

sūta uvāca prastāra ādyago'tho laḥ paratulyo'tha pūrvagaḥ naṣṭamadhye sameṁ'ke laḥ same'rdhe viṣame guruḥ

Suta said: In the Prastara (the table of all possible light-heavy syllable sequences), the first syllable is placed as guru, then light equal to what follows, then equal to what precedes; in the Nashta and Madhya methods, at an even position light is placed, and at an odd position guru.

Verse 2 (garuda.1.212.2)

प्रतिलोमगुणं लाद्यं द्विरुद्दिष्टक एकनुत्

pratilomaguṇaṁ lādyaṁ dviruddiṣṭaka ekanut

In the Uddishtaka method (finding the pattern from a given serial number), light is placed first in reverse order; on doubling the count, when even, one is subtracted.

Verse 3 (garuda.1.212.3)

संख्या द्विरर्धे रूपे तु शून्यं शून्ये द्विरीरितम् । तावदर्धे तद्गुणितं द्विर्द्व्यूनन्तु तदन्ततः

saṁkhyā dvirardhe rūpe tu śūnyaṁ śūnye dvirīritam tāvadardhe tadguṇitaṁ dvirdvyūnantu tadantataḥ

Doubling the halved count, when the remainder is one it is called zero, and when zero it is again doubled; thus halving and multiplying in turn, at the end two are subtracted.

Verse 4 (garuda.1.212.4)

परे पूर्णं परे पूर्णं मेरुः प्रस्तारतो भवेत्

pare pūrṇaṁ pare pūrṇaṁ meruḥ prastārato bhavet

Being full on one side and full on the other, from the Prastara the 'Meru' (the triangular combinatorial table) arises.

Verse 5 (garuda.1.212.5)

लगसंख्या वृत्तसंख्या चाद्याङ्गुलमथोर्ध्वतः । संख्यैव द्विगुणैकोनाच्छन्दः सारोऽयमीरितः

lagasaṁkhyā vṛttasaṁkhyā cādyāṅgulamathordhvataḥ saṁkhyaiva dviguṇaikonācchandaḥ sāro'yamīritaḥ

The count of light-and-heavy syllables and the count of possible meters is reckoned upward from the first unit; this same count, doubled and reduced by one, is declared to be the essence of the science of prosody.