eef1805fe6
* fix: clean-up Project Euler 201-220 * fix: corrections from review Co-authored-by: Tom <20648924+moT01@users.noreply.github.com> Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
47 lines
954 B
Markdown
47 lines
954 B
Markdown
---
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id: 5900f4461000cf542c50ff58
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title: 'Problem 217: Balanced Numbers'
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challengeType: 5
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forumTopicId: 301859
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dashedName: problem-217-balanced-numbers
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---
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# --description--
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A positive integer with $k$ (decimal) digits is called balanced if its first $⌈\frac{k}{2}⌉$ digits sum to the same value as its last $⌈\frac{k}{2}⌉$ digits, where $⌈x⌉$, pronounced ceiling of $x$, is the smallest integer $≥ x$, thus $⌈π⌉ = 4$ and $⌈5⌉ = 5$.
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So, for example, all palindromes are balanced, as is 13722.
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Let $T(n)$ be the sum of all balanced numbers less than $10^n$.
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Thus: $T(1) = 45$, $T(2) = 540$ and $T(5) = 334\\,795\\,890$.
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Find $T(47)\\,mod\\,3^{15}$
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# --hints--
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`balancedNumbers()` should return `6273134`.
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```js
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assert.strictEqual(balancedNumbers(), 6273134);
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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 balancedNumbers() {
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return true;
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}
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balancedNumbers();
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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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