--- id: 5900f4ef1000cf542c510001 title: 'Problem 386: Maximum length of an antichain' challengeType: 5 forumTopicId: 302050 dashedName: problem-386-maximum-length-of-an-antichain --- # --description-- Let n be an integer and S(n) be the set of factors of n. A subset A of S(n) is called an antichain of S(n) if A contains only one element or if none of the elements of A divides any of the other elements of A. For example: S(30) = {1, 2, 3, 5, 6, 10, 15, 30} {2, 5, 6} is not an antichain of S(30). {2, 3, 5} is an antichain of S(30). Let N(n) be the maximum length of an antichain of S(n). Find ΣN(n) for 1 ≤ n ≤ 108 # --hints-- `euler386()` should return 528755790. ```js assert.strictEqual(euler386(), 528755790); ``` # --seed-- ## --seed-contents-- ```js function euler386() { return true; } euler386(); ``` # --solutions-- ```js // solution required ```