documentclass{article}

usepackage{amsmath}
usepackage{amssymb}
usepackage{latexsym}
usepackage{imakeidx} %allows for multiple indexes
usepackage{xcolor}

catcode`"=active
def"#1" {textcolor{white}{#1}} %catcode to color words white, as to hide it on the the compile format

catcode`@=active
def@[#1][#2][#3]@ {#2index[#1]{$square$ "#3" #2}}  %catcode for FORMULAS that are sent to specific indexes as needed, here I use the catcode for "" in order to hide the letter that will allow for the index to be rearranged. so #3 will denote the order of the index, however it will be invisible to the naked eye on white paper so that the formula indexes are easier to read

%making indexes as needed
%  makeindex[name=NICKNAME, title={INDEX_TITLE},columns=1, intoc]

makeindex[name=PV, title={Present Value},columns=1, intoc]

usepackage{lipsum} %creating filler text for demonstration/test purposes

begin{document}

@[PV][$PV$=summation $frac{C}{(1+r)^n}$][c]@
index[PV]{$square  PV = sum frac{C}{(1+r)^n}$}

@[PV][$PV = sum frac{C}{(1+r)^n}$][b]@


indexprologue{Present Value is the discounted value, is the value of an expected income stream determined as of the date of valuation}
printindex[PV]

end{document}