2018-09-30 22:01:58 +00:00
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---
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id: 5900f38a1000cf542c50fe9d
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title: 'Problem 30: Digit n powers'
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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: 301953
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2021-01-13 02:31:00 +00:00
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dashedName: problem-30-digit-n-powers
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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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2020-02-28 12:39:47 +00:00
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2018-09-30 22:01:58 +00:00
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Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:
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2020-02-28 12:39:47 +00:00
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<div style='margin-left: 4em;'>
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1634 = 1<sup>4</sup> + 6<sup>4</sup> + 3<sup>4</sup> + 4<sup>4</sup><br>
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8208 = 8<sup>4</sup> + 2<sup>4</sup> + 0<sup>4</sup> + 8<sup>4</sup><br>
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9474 = 9<sup>4</sup> + 4<sup>4</sup> + 7<sup>4</sup> + 4<sup>4</sup><br>
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</div>
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2018-09-30 22:01:58 +00:00
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As 1 = 1<sup>4</sup> is not a sum it is not included.
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2020-02-28 12:39:47 +00:00
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2018-09-30 22:01:58 +00:00
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The sum of these numbers is 1634 + 8208 + 9474 = 19316.
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2020-02-28 12:39:47 +00:00
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Find the sum of all the numbers that can be written as the sum of `n` powers of their digits.
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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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`digitnPowers(2)` should return a number.
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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(typeof digitnPowers(2) === 'number');
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```
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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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`digitnPowers(2)` should return 0.
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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(digitnPowers(2) == 0);
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```
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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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`digitnPowers(3)` should return 1301.
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```js
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assert(digitnPowers(3) == 1301);
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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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`digitnPowers(4)` should return 19316.
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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(digitnPowers(4) == 19316);
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```
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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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`digitnPowers(5)` should return 443839.
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```js
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assert(digitnPowers(5) == 443839);
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```
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# --seed--
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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 digitnPowers(n) {
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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 n;
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}
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digitnPowers(5);
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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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