// chrome.exe 89.0.4389.90 2021-03-23T16:30:13.069Z function s2n (s) { let pow, n = 0, i = 0 while (i++ < s.length) { pow = Math.pow(26, s.length - i) n += (s.charCodeAt(i - 1) - 97) * pow } return n } function n2s (n) { let s = '' if (!n) s = 'a' else while (n) { s = String.fromCharCode(97 + n % 26) + s n = ~~(n / 26) } return s } function pad (s, n) { while (s.length < n) s = 'a' + s return s } let from = s2n('aaa'), to = s2n('zzz') for (let n = from; n <= to; n++) { console.log(pad(n2s(n), 3)) }