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---
id: 5900f3dd1000cf542c50fef0
title: 'Problem 113: Non-bouncy numbers'
challengeType: 5
forumTopicId: 301739
dashedName: problem-113-non-bouncy-numbers
---
# --description--
Working from left-to-right if no digit is exceeded by the digit to its left it is called an increasing number; for example, 134468.
Similarly if no digit is exceeded by the digit to its right it is called a decreasing number; for example, 66420.
We shall call a positive integer that is neither increasing nor decreasing a "bouncy" number; for example, 155349.
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As n increases, the proportion of bouncy numbers below n increases such that there are only 12951 numbers below one-million that are not bouncy and only 277032 non-bouncy numbers below ${10}^{10}$.
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How many numbers below a googol (${10}^{100}$) are not bouncy?
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# --hints--
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`nonBouncyNumbers()` should return `51161058134250` .
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```js
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assert.strictEqual(nonBouncyNumbers(), 51161058134250);
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```
# --seed--
## --seed-contents--
```js
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function nonBouncyNumbers() {
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return true;
}
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nonBouncyNumbers();
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```
# --solutions--
```js
// solution required
```