25 lines
2.7 KiB
XML
25 lines
2.7 KiB
XML
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<title id="title">到达第i级台阶的两种最后一步</title>
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<desc id="desc">根据教材扫描图人工重绘的矢量教学示意图。文字与线条可无损缩放。</desc>
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<text x="72" y="439.0" text-anchor="middle" dominant-baseline="central" font-size="24" fill="#193b32">f[1]</text>
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<text x="162" y="364.0" text-anchor="middle" dominant-baseline="central" font-size="24" fill="#193b32">f[2]</text>
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<text x="247" y="300.0" text-anchor="middle" dominant-baseline="central" font-size="30" fill="#193b32">⋯</text>
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<text x="347" y="260.0" text-anchor="middle" dominant-baseline="central" font-size="24" fill="#193b32">f[i−2]</text>
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<text x="449" y="178.0" text-anchor="middle" dominant-baseline="central" font-size="24" fill="#193b32">f[i−1]</text>
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<text x="558" y="102.0" text-anchor="middle" dominant-baseline="central" font-size="24" fill="#193b32">f[i]</text>
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<text x="205" y="193.0" text-anchor="end" dominant-baseline="central" font-size="21" fill="#193b32">倒数第1步的步数</text>
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<text x="205" y="250.0" text-anchor="end" dominant-baseline="central" font-size="21" fill="#193b32">倒数第2步的步数</text>
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<text x="386" y="32.3" text-anchor="middle" dominant-baseline="central" font-size="21" fill="#193b32">最后一步</text>
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<text x="386" y="61.7" text-anchor="middle" dominant-baseline="central" font-size="21" fill="#193b32">跨2步</text>
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<text x="566" y="209.3" text-anchor="middle" dominant-baseline="central" font-size="21" fill="#193b32">最后一步</text>
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<text x="566" y="238.7" text-anchor="middle" dominant-baseline="central" font-size="21" fill="#193b32">跨1步</text>
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