In fact, you do not have to be that guy. Different people find different things interesting; just let it go.

True, however, I am also surprised that it's getting this much attention.

There is a little more going on here than basic arithmetic. See the top comment for further evidence: https://news.ycombinator.com/item?id=7144804. But yes, non-math-geeks will probably find this uninteresting. Apparently HN has a lot of math geeks ;)

If more math geeks thought these patterns were religious, we could call this Numerology. We could probably make the case that there are an infinite number of "interesting" patterns that can be generated as the result of "simple" arithmetic. That math geeks assign meaning to these numbers such as as proof of a sane, beautiful universe or a universe with a sense of humor is just human nature.

See also the Interesting number paradox[1].

1. http://en.wikipedia.org/wiki/Interesting_number_paradox

I hope you can see why this example of basic arithmetic is really neat. It reminds us that there are hidden patterns everywhere. Oftentimes, we can determine why the pattern exists with math.

It never hurts to be reminded how cool it is to learn.

After endless stuff on startups, basic arithmetic is a breath of fresh air.

I'd say that hackers are fascinated by neat tricks. Arithmetic tricks are just a subset of those.