<div style="padding:40px;color:#cbccc6"><h1>Ulam 螺旋</h1><p>按螺旋排布整数，标记素数，浮现对角线。</p><div style="padding:20px;background:#0d1017;border-left:3px solid #ffb454"><span class="katex-display"><span class="katex"><span class="katex-html" aria-hidden="true"><span class="mspace newline"></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">t</span><span class="mord mathnormal">e</span><span class="mord mathnormal">x</span><span class="mord mathnormal">t</span><span class="mord"><span class="mord mathnormal">p</span><span class="mord mathnormal" style="margin-right:0.0278em;">r</span><span class="mord mathnormal">im</span><span class="mord mathnormal">e</span></span><span class="mopen">(</span><span class="mord mathnormal">n</span><span class="mclose">)?</span></span></span></span></span></div><p style="color:#707a8c">该页面需要 JavaScript 进行交互式可视化。</p></div>