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curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-273-sum-of-squares.md

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+---
+id: 5900f47e1000cf542c50ff90
+challengeType: 5
+title: 'Problem 273: Sum of Squares'
+forumTopicId: 301923
+---
+
+## Description
+<section id='description'>
+Consider equations of the form: a2 + b2 = N, 0 ≤ a ≤ b, a, b and N integer.
+
+For N=65 there are two solutions:
+a=1, b=8 and a=4, b=7.
+We call S(N) the sum of the values of a of all solutions of a2 + b2 = N, 0 ≤ a ≤ b, a, b and N integer.
+Thus S(65) = 1 + 4 = 5.
+Find ∑S(N), for all squarefree N only divisible by primes of the form 4k+1 with 4k+1 < 150.
+</section>
+
+## Instructions
+<section id='instructions'>
+
+</section>
+
+## Tests
+<section id='tests'>
+
+```yml
+tests:
+  - text: <code>euler273()</code> should return 2032447591196869000.
+    testString: assert.strictEqual(euler273(), 2032447591196869000);
+
+```
+
+</section>
+
+## Challenge Seed
+<section id='challengeSeed'>
+
+<div id='js-seed'>
+
+```js
+function euler273() {
+
+  return true;
+}
+
+euler273();
+```
+
+</div>
+
+
+
+</section>
+
+## Solution
+<section id='solution'>
+
+```js
+// solution required
+```
+
+</section>