Tonight, while doing my quantum mechanics problem set I found that I had to integrate
for arbitrary z-values. If I hadn’t just done about 6 of those manually with specified z-values, I wouldn’t have seen the pattern. A few lines of math and a limit or two and I found its value to be z factorial. This is just a special case of the gamma function, and I had just solved it starting in its integral form.
That was so neat.

Are you somehow able to use LaTeX syntax to get the pretty-looking integrals?
I could do that if I installed the correct plugin, but sadly I have not. Instead, I used a pregenerated image.