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https://liveyourmaths.com/2018/03/14/%ce%b7-%cf%80%ce%b1%ce%b3%ce%ba%cf%8c%cf%83%ce%bc%ce%b9%ce%b1-%ce%b7%ce%bc%ce%ad%cf%81%ce%b1-%cf%84%ce%b7%cf%82-%cf%83%cf%84%ce%b1%ce%b8%ce%b5%cf%81%ce%ac%cf%82-%cf%80/
Η παγκόσμια ημέρα της σταθεράς π!