45 lines
838 B
Markdown
45 lines
838 B
Markdown
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---
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id: 5900f4f11000cf542c510002
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title: 'Problem 388: Distinct Lines'
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challengeType: 5
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forumTopicId: 302052
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dashedName: problem-388-distinct-lines
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---
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# --description--
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Consider all lattice points ($a$, $b$, $c$) with $0 ≤ a, b, c ≤ N$.
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From the origin $O(0, 0, 0)$ all lines are drawn to the other lattice points. Let $D(N)$ be the number of distinct such lines.
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You are given that $D(1\\,000\\,000) = 831\\,909\\,254\\,469\\,114\\,121$.
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Find $D({10}^{10})$. Give as your answer the first nine digits followed by the last nine digits.
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# --hints--
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`distinctLines()` should return `831907372805130000`.
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```js
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assert.strictEqual(distinctLines(), 831907372805130000);
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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 distinctLines() {
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return true;
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}
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distinctLines();
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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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