Item — HN Reader

> But the flag is also studied by mathematicians.

> “It’s the nerdiest mathematical flag that is out there,” Kaye adds.

> In 1962, King Mahendra asked a mathematician to develop precise specifications for the size and shape of the Nepali flag that would be used to standardize the flag. Those specifications are enshrined in Nepal’s constitution.

> Among the rules: the sun must have 12 rays […]

And that’s all we get about the mysterious, mathematical origins of the flag.

It's not very clear what is supposed to be mysterious about it, seems like its just a traditional design. Admittedly the origin is somewhat unclear, but I'm guessing its that more mundane sort of mystery where you don't know something because it was done long ago and you don't know who has a copy of the receipt.