Let's see: The number of my house is [math\] {\frac{1}{\sum\limits_{n = 1}^{\infty}{\frac{1}{n^2)\

Also, the TeX compiler is very fussy about insisting that opening and closing brackets should match up. In the expression {\frac{1}{\sum\limits_{n = 1}^{\infty}{\frac{1}{n^2)\ there are 8 opening braces and only four closing ones. If you correct this imbalance then you should find that the input [tex]\frac{1}{\sum\limits_{n = 1}^{\infty}\frac{1}{n^2}}[/tex] will produce.
Thank you both very much for the input. I'm beginning to realize that writing in LaTex sucks big time! You've got to have hawk eyes to keep track of all those darn round, square, curly parentheses, the slashes and the whole thing...it's awful!
Do you guys happen to know whether there's some program to write
mathematics more or less like html or ASCII and the program then compiles it or translates into Tex?
Thanx
Tonio
TeX/LaTeX is compiled from ASCII, since ASCII has such a restricted character set and is difficult to represent multiple line input is why LaTeX appears so difficult to you.
But it takes only a few hours (using the tutorial and other resources) to become sufficiently proficient to use it on MHF.