I am calculating a recursive equation: $X_n = \frac{1}{2}(X_{n-1} + \frac{3}{X_{n-1}})$
I need a free online calculator that can calculate for $n=7$
$(1/2)\times(88063572/50843527+(3\times 50843527)/88063572)$
and give the answer in rational form. The ones I've tried online do not work as the numbers get too big for the calculators. Wolfram alpha also does not work as it gives me the wrong answer of $X_7 =88063572/50843527$, which is same as $X_6$, so it is wrong.
I put it into Alpha and got $\frac{5170128475599457}{2984975067132296}$