Isaac Argyros
Isaac Argyros (Greek: Ισαάκ Αργυρός) was a Byzantine mathematician and monk, born about 1312, who wrote a treatise named Easter Rule, along with books on arithmetic, geometry and astronomy.
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Wikipedia
Isaac Argyros (Greek: Ισαάκ Αργυρός) was a Byzantine mathematician and monk, born about 1312, who wrote a treatise named Easter Rule, along with books on arithmetic, geometry and astronomy.