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---
id: 5900f4291000cf542c50ff3b
title: 'Problem 188: The hyperexponentiation of a number'
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challengeType: 5
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forumTopicId: 301824
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dashedName: problem-188-the-hyperexponentiation-of-a-number
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---
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# --description--
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The hyperexponentiation or tetration of a number a by a positive integer b, denoted by a↑↑b or ba, is recursively defined by:
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a↑↑1 = a,
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a↑↑(k+1) = a(a↑↑k).
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Thus we have e.g. 3↑↑2 = 33 = 27, hence 3↑↑3 = 327 = 7625597484987 and 3↑↑4 is roughly 103.6383346400240996\*10^12. Find the last 8 digits of 1777↑↑1855.
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# --hints--
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`euler188()` should return 95962097.
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```js
assert.strictEqual(euler188(), 95962097);
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```
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# --seed--
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## --seed-contents--
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```js
function euler188() {
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return true;
}
euler188();
```
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# --solutions--
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```js
// solution required
```
