Stirling numbers of the first kind

Have you ever played with blocks and tried to make different patterns? The stirling numbers of the first kind are like a special way to count how many different patterns you can make with a certain number of blocks.

Let's say you have 3 blocks and you want to know how many different stacks you can make with them. The stirling number of the first kind for n=3 is 2. This means you can make 2 different stacks with 3 blocks.

One stack could be all 3 blocks in a straight line, like this:

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The other stack could be two blocks on the bottom and one on top, like this:

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Stirling numbers of the first kind help us count the number of unique ways we can order items in a sequence. They come in handy when we want to solve problems that involve ordering things in a specific way.