I take it you mean that , , , and .

Did you forget to do the sum? Take what you got for k=0 (before "cross multiplying") and add it to the result for k= 1. THEN "cross multiply" to find the next approximation to .After A, B, and D are calculated by sending a number k=0 through the series (not C, because it is what represents Pi) I proceed to cross multiply to solve for C. I get A*D = B*C

I divide by B, so really, C = AD/B

The output is 3.14159265358973420766845359157829834076… (accurate to 13 digits after the decimal place).

If I go through the series again and repeat the cross multiplication for the next number, k=1, then the output is -167194165969664.18081570948421477548969…

That " " is a standard symbol for "sum". But you addNow, at this point, should I be multiplying my values of C from previous itterations? Or should I be adding them? Or is something wrong with my calculation. Thank you for the advice!before"cross multiplying" to get C.