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Comment by mrcactu5 | Hacker News Reader

Here's some notes from Harvard on how to count Rubik's Cube positions with Group Theory

The number is: 2^(12)3^88!*12!

http://www.math.harvard.edu/~jjchen/docs/Group%20Theory%20an...

I know mathematicians hate interpunction with a passion but that one's pretty extreme! I have no idea where the timeses and the parentheses are supposed to go..

! has operator precedence over \

It's not helped by the fact than HN markup is interpreting asterisks as requests for italics and backslashes as escape sequences...

The fact that HN still doesn't have a proper way to display code or mathematical formulas after all these years is a bit ridiculous. I guess by now it's part of the website's culture...

I'd prefer real markdown, but iirc 4 spaces of indentation does it?
Foo*bar

Two: https://news.ycombinator.com/formatdoc

Does anyone know where to find a guide to HN markup? I've exhausted my google-fu and have come up dry...

There's a short one here: https://news.ycombinator.com/formatdoc

Thanks!

It's 2^12 × 3^8 × 8! × 12!

To go full Unicode: 2¹² × 3⁸ × 8! × 12!

12!9!(4!3!)³

Perhaps someone can tell us how many digits that has (or am expression for how many digits...)

Its explicit value is 519024039293878272000 (not nearly as big as some integers we discuss around here!).

Or roughly 5.2E20, if you're just looking for the order of magnitude.
Or ~520 exapositions, if you want to say it in a way that upsets people.

451 exapositions, if you want to say it in a way that really upsets people.

451 "exbipositions" should calm some of those people down (and further antagonize others).
https://en.wikipedia.org/wiki/Binary_prefix#exbi
BTW don't bother Googling for exaposition or exbiposition. :-)

It's pretty much impossible to decipher if you don't remember the operator precedence or have the operator precendence handy.

The same paper also states that they calculated the number above earlier, but only about 1/12th of those are valid so the real number of valid combinations is 4x10^19

Looks like you might need to put spaces between * and other text because the auto-italicization thing is gobbling your multiplication.

2 spaces prefix for verbatim

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