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---
id: 5900f4af1000cf542c50ffc1
title: 'Problem 322: Binomial coefficients divisible by 10'
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challengeType: 5
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forumTopicId: 301979
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dashedName: problem-322-binomial-coefficients-divisible-by-10
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---
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# --description--
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Let $T(m, n)$ be the number of the binomial coefficients ${}^iC_n$ that are divisible by 10 for $n ≤ i < m$ ($i$, $m$ and $n$ are positive integers).
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You are given that $T({10}^9, {10}^7 - 10) = 989\\,697\\,000$.
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Find $T({10}^{18}, {10}^{12} - 10)$.
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# --hints--
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`binomialCoefficientsDivisibleBy10()` should return `999998760323314000` .
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```js
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assert.strictEqual(binomialCoefficientsDivisibleBy10(), 999998760323314000);
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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 binomialCoefficientsDivisibleBy10() {
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return true;
}
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binomialCoefficientsDivisibleBy10();
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```
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# --solutions--
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```js
// solution required
```
