2018-09-30 22:01:58 +00:00
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---
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id: 5900f48f1000cf542c50ffa2
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title: 'Problem 291: Panaitopol Primes'
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2020-11-27 18:02:05 +00:00
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challengeType: 5
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2019-08-05 16:17:33 +00:00
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forumTopicId: 301943
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2021-01-13 02:31:00 +00:00
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dashedName: problem-291-panaitopol-primes
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2018-09-30 22:01:58 +00:00
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---
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2020-11-27 18:02:05 +00:00
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# --description--
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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A prime number p is called a Panaitopol prime if for some positive integersx and y.
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2018-09-30 22:01:58 +00:00
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Find how many Panaitopol primes are less than 5×1015.
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2020-11-27 18:02:05 +00:00
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# --hints--
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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`euler291()` should return 4037526.
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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```js
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assert.strictEqual(euler291(), 4037526);
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2018-09-30 22:01:58 +00:00
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```
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2020-11-27 18:02:05 +00:00
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# --seed--
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2018-09-30 22:01:58 +00:00
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2020-11-27 18:02:05 +00:00
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## --seed-contents--
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2018-09-30 22:01:58 +00:00
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```js
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function euler291() {
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2020-09-15 16:57:40 +00:00
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2018-09-30 22:01:58 +00:00
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return true;
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}
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euler291();
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```
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2020-11-27 18:02:05 +00:00
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# --solutions--
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2018-09-30 22:01:58 +00:00
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```js
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// solution required
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```
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