49 lines
1.2 KiB
Markdown
49 lines
1.2 KiB
Markdown
---
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id: 5900f39f1000cf542c50feb2
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title: 'Problem 51: Prime digit replacements'
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challengeType: 5
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forumTopicId: 302162
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dashedName: problem-51-prime-digit-replacements
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---
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# --description--
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By replacing the 1st digit of the 2-digit number \*3, it turns out that six of the nine possible values: 13, 23, 43, 53, 73, and 83, are all prime.
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By replacing the 3rd and 4th digits of 56\*\*3 with the same digit, this 5-digit number is the first example having seven primes among the ten generated numbers, yielding the family: 56003, 56113, 56333, 56443, 56663, 56773, and 56993. Consequently 56003, being the first member of this family, is the smallest prime with this property.
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Find the smallest prime which, by replacing part of the number (not necessarily adjacent digits) with the same digit, is part of an eight prime value family.
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# --hints--
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`primeDigitReplacements()` should return a number.
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```js
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assert(typeof primeDigitReplacements() === 'number');
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```
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`primeDigitReplacements()` should return 121313.
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```js
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assert.strictEqual(primeDigitReplacements(), 121313);
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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 primeDigitReplacements() {
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return true;
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}
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primeDigitReplacements();
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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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