# Resources to learn the meaning of any math symbol

There is lots of symbols and may be operators like || in this expression

$$3^k||n$$

that I would like to be able to quickly find the meaning of. I tried Wolfram|Alpha but I think it expects the name of the symbol instead of the symbol itself, so it doesn't give me the correct answer.

Some resources you could recommend?

Thanks!

• The source wheer you find that expression should introduce notation that is not to usual (and sometimes invented by the author). Of gourse $a||b$ may mean that two lines are parallel in geometry, whereas in number theory it has - no meaning. Instead this is really a ternary relation: $a^b||c$ means that $c$ is a multiple of $a^b$ but not of $a^{b+1}$. This doesn't help you in decrypting general symbolism, though. – Hagen von Eitzen Sep 29 '12 at 9:35
• @Hagen - I guess Adrián saw it in the document referred to in this answer. Unfortunately this assumes a rather advanced level from the reader, and familiarity with notation, so symbols and operators aren't explained there. – stevenvh Sep 29 '12 at 10:05
• @stevenvh: Yes, I see the natural dilemma. Advanced texts assume advanced familiarity. Then again, they should not be the first texts in an area one encounters and all unexplained notation should be established notation, hence anybody prepared enough to read the advanced text should have read enough introductory texts which - hopefully - introduce standrd notation. Notation aside, a text about special aspects of the Riemann hypothesis will typically not explain in detail what a prime or a meromorphic function or the relation between $s$, $t$ and $\sigma$ is. It remains a dilemma though. – Hagen von Eitzen Sep 29 '12 at 11:04
• @HagenvonEitzen Thanks for the answer to that symbol. Shame I can not vote a comment :/ – Adrián Pérez Sep 29 '12 at 13:14
• @stevenvh Yes, that's the document I was reading. I wanted to know the answer to that apparently easy problem, and got stuck in that expression. This monday I start my first year of the degree in computer science, and I wanted to improve my maths. The most interesting things I could find are all wrote in math notation. If I knew lots of this notation and maths I would create a webapp to add math symbols and descriptions and offer symbol lookup, so every one interested could decypher this kind of expressions – Adrián Pérez Sep 29 '12 at 13:14