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---
id: 5900f4521000cf542c50ff64
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title: 'Problema 229: Quatro representações usando quadrados'
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challengeType: 5
forumTopicId: 301872
dashedName: problem-229-four-representations-using-squares
---
# --description--
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Considere o número 3600. Ele é muito especial, porque
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$$\begin{align} & 3600 = {48}^2 + {36}^2 \\\\
& 3600 = {20}^2 + {2× 40}^2 \\\\ & 3600 = {30}^2 + {3× 30}^2 \\\\
& 3600 = {45}^2 + {7× 15}^2 \\\\ \end{align}$$
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Da mesma forma, descobrimos que $88201 = {99}^2 + {280}^2 = {287}^2 + 2 × {54}^2 = {283}^2 + 3 × {52}^2 = {197}^2 + 7 × {84}^2$.
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Em 1747, Euler provou quais números são representáveis como uma soma de dois quadrados. Estamos interessados nos números $n$ que admitem representações de todos os quatro tipos a seguir:
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$$\begin{align} & n = {a_1}^2 + {b_1}^2 \\\\
& n = {a_2}^2 + 2{b_2}^2 \\\\ & n = {a_3}^2 + 3{b_3}^2 \\\\
& n = {a_7}^2 + 7{b_7}^2 \\\\ \end{align}$$
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onde $a_k$ e $b_k$ são números inteiros positivos.
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Há 75373 números que não excedem ${10}^7$.
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Quantos desses números existem e que não excedam $2 × {10}^9$?
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# --hints--
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`representationsUsingSquares()` deve retornar `11325263` .
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```js
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assert.strictEqual(representationsUsingSquares(), 11325263);
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```
# --seed--
## --seed-contents--
```js
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function representationsUsingSquares() {
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return true;
}
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representationsUsingSquares();
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```
# --solutions--
```js
// solution required
```