MATLAB: Approximating Pi by Using Ramanujan’s Formula

coding

Hi. This is my first post so please let me know if I violate any kind of rules. Thank you in advance.
I intend to approximate pi by summing a specified number of terms (k). The output I got was nowhere near what I wanted. Could someone help me please?
Here is the equation I'm using:
And there is the code:
k = input('Number of terms: ');
pi2 = sum(factorial([1:k]*4).*(1103+26390*[1:k]));
pi2 = pi2/((factorial([1:k])^4)*396^(4*[1:k]));
pi2 = (pi2*(2*sqrt(2)/9801))^(-1);
fprintf('Method: %.20f\n', pi2);

Best Answer

>> k = 5;
>> V = 0:k;
>> N = factorial(4.*V).*(1103+26390.*V);
>> D = (factorial(V).^4).*(396.^(4.*V));
>> (2*sqrt(2)/9801)*sum(N./D)
ans =    3.183098861837907e-01
>> 1./pi
ans =    3.183098861837907e-01
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