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	<title>2018 &#8211; Problems in Mathematics</title>
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	<title>2018 &#8211; Problems in Mathematics</title>
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		<title>Mathematics About the Number 2018</title>
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				<pubDate>Mon, 01 Jan 2018 05:01:59 +0000</pubDate>
		<dc:creator><![CDATA[Yu]]></dc:creator>
				<category><![CDATA[General]]></category>
		<category><![CDATA[2018]]></category>
		<category><![CDATA[prime number]]></category>
		<category><![CDATA[sum of cubes]]></category>
		<category><![CDATA[sum of squares]]></category>

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				<description><![CDATA[<p>Happy New Year 2018!! Here are several mathematical facts about the number 2018. &#160; Is 2018 a Prime Number? The number 2018 is an even number, so in particular 2018 is not a prime&#46;&#46;&#46;</p>
<p>The post <a href="https://yutsumura.com/mathematics-about-the-number-2018/" target="_blank">Mathematics About the Number 2018</a> first appeared on <a href="https://yutsumura.com/" target="_blank">Problems in Mathematics</a>.</p>]]></description>
								<content:encoded><![CDATA[<p>Happy New Year 2018!!</p>
<p>Here are several mathematical facts about the number 2018.</p>
<p>&nbsp;<br />
<span id="more-6646"></span><br />

<h2>Is 2018 a Prime Number? </h2>
<p>The number 2018 is an even number, so in particular 2018 is not a prime number.<br />
The prime factorization of 2018 is<br />
\[2018=2\cdot 1009.\]
Here $2$ and $1009$ are prime numbers.</p>
<h2>Identities for 2018 </h2>
<p>Here are some identities for 2018.</p>
<h3>2018 is the sum of two squares</h3>
<p>2018 is the sum of two squares:<br />
\begin{align*}<br />
2018=13^2+43^2.<br />
\end{align*}<br />
Here are some variants.<br />
\begin{align*}<br />
2018&#038;=1^2+9^2+44^2\\<br />
2018&#038;=1^2+12^2+28^2+33^2\\<br />
2018&#038;=2^2+2^2+5^2+7^2+44^2\\<br />
2018&#038;=6^2+2(29)^2+3(10)^2<br />
\end{align*}</p>
<h3>2018 is a part of a Pythagorean triple</h3>
<p>2018 is a part of a Pythagorean triple:<br />
\begin{align*}<br />
2018^2=1118^2+1680^2.<br />
\end{align*}</p>
<p>This means that there is a right triangle whose hypotenuse is 2018.<br />
<img src="https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?resize=600%2C600&#038;ssl=1" alt="2018 is a part of Pythagorean triple" width="600" height="600" class="alignnone size-full wp-image-6652" srcset="https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?w=600&amp;ssl=1 600w, https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?resize=150%2C150&amp;ssl=1 150w, https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?resize=300%2C300&amp;ssl=1 300w, https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?resize=160%2C160&amp;ssl=1 160w, https://i2.wp.com/yutsumura.com/wp-content/uploads/2017/12/triangle2018.png?resize=320%2C320&amp;ssl=1 320w" sizes="(max-width: 600px) 100vw, 600px" data-recalc-dims="1" /></p>
<p>Here are some variants.<br />
\begin{align*}<br />
2018^2&#038;=18^2+88^2+2016^2\\<br />
2018^2&#038;=460^2+566^2+1172^2+1472^2\\<br />
2018^3&#038;=421^3+1490^3+1691^3<br />
\end{align*}</p>
<h2>2018 is the sum of 12 successive integers</h2>
<p>2018 is the sum of 12 successive integers:<br />
\[2018=7^2+8^2+9^2+10^2+11^2+12^2+13^2+14^2+15^2+16^2+17^2+18^2.\]
<h2>2018 appears in $\pi=3.14&#8230;$</h2>
<p>2018 appears in the number $\pi=3.14&#8230;$ as in the following picture.<br />
<img src="https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?resize=600%2C600&#038;ssl=1" alt="2018 appears in pi" width="600" height="600" class="alignnone size-full wp-image-6649" srcset="https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?w=600&amp;ssl=1 600w, https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?resize=150%2C150&amp;ssl=1 150w, https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?resize=300%2C300&amp;ssl=1 300w, https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?resize=160%2C160&amp;ssl=1 160w, https://i0.wp.com/yutsumura.com/wp-content/uploads/2017/12/pi2018.png?resize=320%2C320&amp;ssl=1 320w" sizes="(max-width: 600px) 100vw, 600px" data-recalc-dims="1" /></p>
<h2>How about 2017? </h2>
<p>Did you miss mathematical facts about 2017?</p>
<p>Check out</p>
<p><a href="https://yutsumura.com/mathematics-about-the-number-2017/"></a></p>
<button class="simplefavorite-button has-count" data-postid="6646" data-siteid="1" data-groupid="1" data-favoritecount="46" style="">Click here if solved <i class="sf-icon-star-empty"></i><span class="simplefavorite-button-count" style="">46</span></button><p>The post <a href="https://yutsumura.com/mathematics-about-the-number-2018/" target="_blank">Mathematics About the Number 2018</a> first appeared on <a href="https://yutsumura.com/" target="_blank">Problems in Mathematics</a>.</p>]]></content:encoded>
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