2018-10-10 18:03:03 -04:00
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---
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id: 5900f4531000cf542c50ff66
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2021-02-06 04:42:36 +00:00
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title: 'Problem 231: The prime factorisation of binomial coefficients'
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2018-10-10 18:03:03 -04:00
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challengeType: 5
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2021-02-06 04:42:36 +00:00
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forumTopicId: 301875
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2021-01-13 03:31:00 +01:00
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dashedName: problem-231-the-prime-factorisation-of-binomial-coefficients
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2021-02-06 04:42:36 +00:00
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The binomial coefficient 10C3 = 120.
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2018-10-10 18:03:03 -04:00
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2021-02-06 04:42:36 +00:00
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120 = 23 × 3 × 5 = 2 × 2 × 2 × 3 × 5, and 2 + 2 + 2 + 3 + 5 = 14.
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So the sum of the terms in the prime factorisation of 10C3 is 14.
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Find the sum of the terms in the prime factorisation of 20000000C15000000.
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2021-02-06 04:42:36 +00:00
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`euler231()` should return 7526965179680.
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert.strictEqual(euler231(), 7526965179680);
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2018-10-10 18:03:03 -04:00
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```
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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function euler231() {
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return true;
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}
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euler231();
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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```js
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// solution required
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```
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