--- id: 5900f4cb1000cf542c50ffde title: 'Problem 351: Hexagonal orchards' challengeType: 5 forumTopicId: 302011 dashedName: problem-351-hexagonal-orchards --- # --description-- A hexagonal orchard of order n is a triangular lattice made up of points within a regular hexagon with side n. The following is an example of a hexagonal orchard of order 5: Highlighted in green are the points which are hidden from the center by a point closer to it. It can be seen that for a hexagonal orchard of order 5, 30 points are hidden from the center. Let H(n) be the number of points hidden from the center in a hexagonal orchard of order n. H(5) = 30. H(10) = 138. H(1 000) = 1177848. Find H(100 000 000). # --hints-- `euler351()` should return 11762187201804552. ```js assert.strictEqual(euler351(), 11762187201804552); ``` # --seed-- ## --seed-contents-- ```js function euler351() { return true; } euler351(); ``` # --solutions-- ```js // solution required ```