49 lines
845 B
Markdown
49 lines
845 B
Markdown
---
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id: 5900f4181000cf542c50ff2a
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title: >-
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Problem 171: Finding numbers for which the sum of the squares of the digits is a square
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challengeType: 5
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forumTopicId: 301806
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dashedName: >-
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problem-171-finding-numbers-for-which-the-sum-of-the-squares-of-the-digits-is-a-square
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---
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# --description--
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For a positive integer n, let f(n) be the sum of the squares of the digits (in base 10) of n, e.g.
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f(3) = 32 = 9,
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f(25) = 22 + 52 = 4 + 25 = 29,
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f(442) = 42 + 42 + 22 = 16 + 16 + 4 = 36
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Find the last nine digits of the sum of all n, 0 < n < 1020, such that f(n) is a perfect square.
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# --hints--
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`euler171()` should return 142989277.
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```js
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assert.strictEqual(euler171(), 142989277);
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```
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# --seed--
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## --seed-contents--
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```js
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function euler171() {
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return true;
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}
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euler171();
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```
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# --solutions--
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```js
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// solution required
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```
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