--- id: 5900f4e81000cf542c50fffa title: 'Problem 379: Least common multiple count' challengeType: 5 forumTopicId: 302041 dashedName: problem-379-least-common-multiple-count --- # --description-- Let $f(n)$ be the number of couples ($x$, $y$) with $x$ and $y$ positive integers, $x ≤ y$ and the least common multiple of $x$ and $y$ equal to $n$. Let $g$ be the summatory function of $f$, i.e.: $g(n) = \sum f(i)$ for $1 ≤ i ≤ n$. You are given that $g({10}^6) = 37\\,429\\,395$. Find $g({10}^{12})$. # --hints-- `leastCommonMultipleCount()` should return `132314136838185`. ```js assert.strictEqual(leastCommonMultipleCount(), 132314136838185); ``` # --seed-- ## --seed-contents-- ```js function leastCommonMultipleCount() { return true; } leastCommonMultipleCount(); ``` # --solutions-- ```js // solution required ```