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---
id: 5900f4381000cf542c50ff4a
title: 'Problem 203: Squarefree Binomial Coefficients'
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challengeType: 5
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forumTopicId: 301844
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dashedName: problem-203-squarefree-binomial-coefficients
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---
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# --description--
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The binomial coefficients $\displaystyle\binom{n}{k}$ can be arranged in triangular form, Pascal's triangle, like this:
$$\begin{array}{ccccccccccccccc}
& & & & & & & 1 & & & & & & & \\\\
& & & & & & 1 & & 1 & & & & & & \\\\
& & & & & 1 & & 2 & & 1 & & & & & \\\\
& & & & 1 & & 3 & & 3 & & 1 & & & & \\\\
& & & 1 & & 4 & & 6 & & 4 & & 1 & & & \\\\
& & 1 & & 5 & & 10 & & 10 & & 5 & & 1 & & \\\\
& 1 & & 6 & & 15 & & 20 & & 15 & & 6 & & 1 & \\\\
1 & & 7 & & 21 & & 35 & & 35 & & 21 & & 7 & & 1 \\\\
& & & & & & & \ldots
\end{array}$$
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It can be seen that the first eight rows of Pascal's triangle contain twelve distinct numbers: 1, 2, 3, 4, 5, 6, 7, 10, 15, 20, 21 and 35.
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A positive integer n is called squarefree if no square of a prime divides n. Of the twelve distinct numbers in the first eight rows of Pascal's triangle, all except 4 and 20 are squarefree. The sum of the distinct squarefree numbers in the first eight rows is 105.
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Find the sum of the distinct squarefree numbers in the first 51 rows of Pascal's triangle.
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# --hints--
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`squarefreeBinomialCoefficients()` should return `34029210557338` .
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```js
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assert.strictEqual(squarefreeBinomialCoefficients(), 34029210557338);
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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 squarefreeBinomialCoefficients() {
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return true;
}
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squarefreeBinomialCoefficients();
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```
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# --solutions--
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```js
// solution required
```