--- id: 5900f3a01000cf542c50feb3 title: 'Problem 52: Permuted multiples' challengeType: 5 forumTopicId: 302163 dashedName: problem-52-permuted-multiples --- # --description-- It can be seen that the number, 125874, and its double, 251748, contain exactly the same digits, but in a different order. Find the smallest positive integer, such that multiplied by integers $\\{2, 3, \ldots, n\\}$, contain the same digits. # --hints-- `permutedMultiples(2)` should return a number. ```js assert(typeof permutedMultiples(2) === 'number'); ``` `permutedMultiples(2)` should return `125874`. ```js assert.strictEqual(permutedMultiples(2), 125874); ``` `permutedMultiples(6)` should return `142857`. ```js assert.strictEqual(permutedMultiples(6), 142857); ``` # --seed-- ## --seed-contents-- ```js function permutedMultiples(n) { return true; } permutedMultiples(2); ``` # --solutions-- ```js function permutedMultiples(n) { const isPermutation = (a, b) => a.length !== b.length ? false : a.split('').sort().join() === b.split('').sort().join(); let start = 1; let found = false; let result = 0; while (!found) { start *= 10; for (let i = start; i < start * 10 / n; i++) { found = true; for (let j = 2; j <= n; j++) { if (!isPermutation(i + '', j * i + '')) { found = false; break; } } if (found) { result = i; break; } } } return result; } ```