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  <blog_title>hsjoihs’s diary</blog_title>
  <blog_url>https://hsjoihs.hatenablog.com/</blog_url>
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  <description>概要 http://sketch.txt-nifty.com/blog/2008/12/post-cb2c.htmlによれば、ファミコン音源の「三角波」は実は16段階の階段状で、F E D C B A 9 8 7 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 A B C D E F の繰り返しを出力するそうだ。なるほどね。 ということでフーリエ級数展開してみよう。周期$t_0$の三角波の一周期分は$\left\{0&lt;x&lt;\frac{t_{0}}{2}:-1+\frac{4x}{t_{0}},\frac{t_{0}}{2}&lt;x&lt;t_{0}:3-\frac{4x}{t_{0}…</description>
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  <provider_name>Hatena Blog</provider_name>
  <provider_url>https://hatena.blog</provider_url>
  <published>2020-09-04 15:41:44</published>
  <title>ファミコン疑似三角波のフーリエ級数展開</title>
  <type>rich</type>
  <url>https://hsjoihs.hatenablog.com/entry/2020/09/04/154144</url>
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