freeCodeCamp/curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-326-modulo-summations.md

---
id: 5900f4b21000cf542c50ffc5
title: 'Problem 326: Modulo Summations'
challengeType: 5
forumTopicId: 301983
dashedName: problem-326-modulo-summations
---

# --description--

Let an be a sequence recursively defined by: .

So the first 10 elements of an are: 1,1,0,3,0,3,5,4,1,9.

Let f(N,M) represent the number of pairs (p,q) such that:

It can be seen that f(10,10)=4 with the pairs (3,3), (5,5), (7,9) and (9,10).

You are also given that f(104,103)=97158.

Find f(1012,106).

# --hints--

`euler326()` should return 1966666166408794400.

```js
assert.strictEqual(euler326(), 1966666166408794400);
```

# --seed--

## --seed-contents--

```js
function euler326() {

  return true;
}

euler326();
```

# --solutions--

```js
// solution required
```