freeCodeCamp/curriculum/challenges/english/08-coding-interview-prep/project-euler/problem-422-sequence-of-poi...

1.5 KiB

id challengeType title
5900f5131000cf542c510025 5 Problem 422: Sequence of points on a hyperbola

Description

Let H be the hyperbola defined by the equation 12x2 + 7xy - 12y2 = 625.

Next, define X as the point (7, 1). It can be seen that X is in H.

Now we define a sequence of points in H, {Pi : i ≥ 1}, as: P1 = (13, 61/4). P2 = (-43/6, -4). For i > 2, Pi is the unique point in H that is different from Pi-1 and such that line PiPi-1 is parallel to line Pi-2X. It can be shown that Pi is well-defined, and that its coordinates are always rational. You are given that P3 = (-19/2, -229/24), P4 = (1267/144, -37/12) and P7 = (17194218091/143327232, 274748766781/1719926784).

Find Pn for n = 1114 in the following format:If Pn = (a/b, c/d) where the fractions are in lowest terms and the denominators are positive, then the answer is (a + b + c + d) mod 1 000 000 007.

For n = 7, the answer would have been: 806236837.

Instructions

Tests

tests:
  - text: <code>euler422()</code> should return 92060460.
    testString: assert.strictEqual(euler422(), 92060460, '<code>euler422()</code> should return 92060460.');

Challenge Seed

function euler422() {
  // Good luck!
  return true;
}

euler422();

Solution

// solution required