freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/project-euler/problem-420-2x2-positive-integer-matrix.english.md

id	challengeType	title
5900f5111000cf542c510023	5	Problem 420: 2x2 positive integer matrix

Description

A positive integer matrix is a matrix whose elements are all positive integers. Some positive integer matrices can be expressed as a square of a positive integer matrix in two different ways. Here is an example:

We define F(N) as the number of the 2x2 positive integer matrices which have a trace less than N and which can be expressed as a square of a positive integer matrix in two different ways. We can verify that F(50) = 7 and F(1000) = 1019.

Find F(107).

Instructions

Tests

tests:
  - text: <code>euler420()</code> should return 145159332.
    testString: assert.strictEqual(euler420(), 145159332, '<code>euler420()</code> should return 145159332.');

Challenge Seed

function euler420() {
  // Good luck!
  return true;
}

euler420();

Solution

// solution required