--- id: 5900f49b1000cf542c50ffae title: 'Problem 303: Multiples with small digits' challengeType: 5 forumTopicId: 301957 dashedName: problem-303-multiples-with-small-digits --- # --description-- For a positive integer $n$, define $f(n)$ as the least positive multiple of $n$ that, written in base 10, uses only digits $≤ 2$. Thus $f(2) = 2$, $f(3) = 12$, $f(7) = 21$, $f(42) = 210$, $f(89) = 1\\,121\\,222$. Also, $\displaystyle\sum_{n = 1}^{100} \frac{f(n)}{n} = 11\\,363\\,107$. Find $\displaystyle\sum_{n = 1}^{10\\,000} \frac{f(n)}{n}$. # --hints-- `multiplesWithSmallDigits()` should return `1111981904675169`. ```js assert.strictEqual(multiplesWithSmallDigits(), 1111981904675169); ``` # --seed-- ## --seed-contents-- ```js function multiplesWithSmallDigits() { return true; } multiplesWithSmallDigits(); ``` # --solutions-- ```js // solution required ```