That there are two colors per strut, so what's linking the two backbones together are two colored segments that come from the outside towards the middle, and that the colors occur only in certain combinations, red and green, yellow and blue, that's all you see.

每个梯阶有两个颜色,主链是由,两种不同颜色的片段由外向内连接起来的,这些颜色仅以某种特定方式配对,红连接绿,黄连接蓝,大家都能看到

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And we can generalize to figure out, based on any principle quantum number n, how many orbitals we have of the same energy, n and what we can say is that for any shell n, there are n squared degenerate orbitals.

我们可以总结出来，在，主量子数为n的情况下，同一个能量上，有多少个轨道，我们可以说，对任何壳层，有n平方个简并轨道。

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