Hello. This is an otherwise senseless demo of a preliminary version of a
typesetting apparatus, from a flat file in tex to conventional
mathematical notation, written in java. Fraction
$\pi^2\rightarrow\int_0 {A_i+B^{2^{t+\pi}} \over B+({{3-x^2} \over
{x^3-{1 \over y}}}) } $ and then nothing.  Ok, first we have some
plain verbiage, and a simple markup $x^2$, and then here it is, oops,
not yet, we want to have at least two lines between... ok maybe now
we've written enough, let's see : $x^{2+C^3}=q^{1+D^7} =A^{1+B^{5+r^{2}}}$ and then
let's get to the next line perhaps:
$y^{1+2^{t+23}} = w_{a_{b_c}}$.  And then back to plain text to show how it wraps and
compensates (modestly, at least).
Ok. No restriction on the number of superscripts and/or
subscripts. They're vertically aligned if both
occur attached to the same primary object. Easy enough to fix!  Before
the TeX stuff starts, we'll have a line of plain text. Then, just to
see, we'll have simple: and $y_{2_{3_4}}$. And $x^{2^{t^4}}$ then
we'll have more lines to see what happens. And some more. And
more. And let's continue a bit further to compare the interline
spacing with or without subscripting.
Well, verbiage for a while here, long enough to get a wrap-around, and
then have the superscripts underneath, looking out for overlap, etc.
$X^{1+X^{2+X^{3+X}}}$ is the last part.
Fraction $ {A+B^2} \over {B+{3 \over {x^3-1}}} $ and then nothing.
Fraction $ {{M+y} \over {M-y}}  = M^{y+M} = y_{M-y}$.