The number of combinations for matra meters are stated [as follows]. The sum (योगः) of the last and last-but-one (अन््त्ययौपान््ततौ) terms is the number of meters possible for a given number of matras.

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Source: अथ मात्राविकल््पपानां संख््ययामाह -अङ्कान््त्ययोपान््त््ययोगः परे परे मात्राणाम॥् १६॥अङ्कानामेकद््वव््ययादीनां यौ अन््त्ययौपान््त्ययौ तयोर्योगःपरस््परमीलनं परे परे स््थथाने न््यस््ततौ मात्राणां संख््यया भवति।
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