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This verse encrypts the value of pi (π) up to 31 decimal places.

गोपीभाग्यमधुव्रात-शृङ्गिशोदधिसन्धिग॥ खलजीवितखाताव गलहालारसंधर॥

... <Malyalam shloka/poem> This verse directly yields the decimal equivalent of pi divided by 10: pi/10 = 0.31415926535897932384626433832792

This link goes into more details of this one shloka/poem

https://www.speakingtree.in/allslides/encryption-in-ancient-...