--- id: 5900f4551000cf542c50ff68 title: 'Problem 233: Lattice points on a circle' challengeType: 5 forumTopicId: 301877 dashedName: problem-233-lattice-points-on-a-circle --- # --description-- Let $f(N)$ be the number of points with integer coordinates that are on a circle passing through $(0,0)$, $(N,0)$,$(0,N)$, and $(N,N)$. It can be shown that $f(10000) = 36$. What is the sum of all positive integers $N ≤ {10}^{11}$ such that $f(N) = 420$? # --hints-- `latticePointsOnACircle()` should return `271204031455541300`. ```js assert.strictEqual(latticePointsOnACircle(), 271204031455541300); ``` # --seed-- ## --seed-contents-- ```js function latticePointsOnACircle() { return true; } latticePointsOnACircle(); ``` # --solutions-- ```js // solution required ```