Centered hexagonal number
Okay kiddo, imagine you have a bunch of hexagons (which are six-sided shapes). Now imagine you put one hexagon in the middle and then surround it with more hexagons, making a bigger hexagon. You keep doing this over and over again, making bigger and bigger hexagons with one hexagon in the very center.
When you count how many hexagons are in each bigger hexagon, you end up with a sequence of numbers that starts 1, 7, 19, 37, and so on. These are called centered hexagonal numbers because they are made up of hexagons centered around one hexagon in the middle.
It's kind of like building a tower with blocks, but instead of making a straight tower, you're making a tower where each level has one block in the middle and then more blocks around it to make a bigger level.
So, the centered hexagonal number is just the number of hexagons you have in the largest hexagon you can make using this process.
When you count how many hexagons are in each bigger hexagon, you end up with a sequence of numbers that starts 1, 7, 19, 37, and so on. These are called centered hexagonal numbers because they are made up of hexagons centered around one hexagon in the middle.
It's kind of like building a tower with blocks, but instead of making a straight tower, you're making a tower where each level has one block in the middle and then more blocks around it to make a bigger level.
So, the centered hexagonal number is just the number of hexagons you have in the largest hexagon you can make using this process.
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