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<h1>Welcome</h1> 

<marquee behavior="" direction="left">**Hello world**, this is my first Jekyll blog post.</marquee>

<p>I hope you like it!</p>
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\(\mathcal{L}\left\{ {af\left( t \right) + bg\left( t \right)} \right\} = a\,F\left( s \right) + b\,G\left( s \right)\)