decimal numerical numeral pi field integer quantitative glyph alphanumeric keypad 1 hexadecimal ring encrypted alphabetic coded fraction euler set polynomial infinity counting measurement symbol isbn mathematics calculation addition multiplication division exponentiation arithmetic pseudoscience numerology 2 3 4 circa egypt 0 china sanskrit subtraction philosophical vacuum olmec 13 mexico 1,000,000 ptolemy hipparchus omicron easter bede coefficient greece india byte pāṇini europe fibonacci predefined exponent authentication binary prefixed identifiers ascii sexagesimal bcd encode scsi encoding bytes keywords alphabetical pythagoras codes unicode digits abbreviations dichotomous domains password phonetic tags formatting template parameter dialing euclid compute decoding superscript meanings suffixes prefixes redirection notation pointers