Plotting a power series

I want to plot a power series with the first non zero term, sum of the first two terms, up to a sum of terms defined by the for loop. I am confused how to add each sum because when I try g(n+1)=g(n)+ series it tells me the number of elements in A and B must be the same. The original function is: 10*cos(50t). I have found the series as seen inside the for loop but it does not plot the summations

 clear;
 N=400;
 prompt = ('Enter number of  terms to sum: ');   
 i=input(prompt);   

 t=linspace(0,300,N+1);
 f=10*cos(50*t);

 g=zeros(1,N+1);

 for n=1:i
    g = g + ((-1)^n * (2500^n) * t.^(2*n)/(2*factorial(n)))
 end

 hold on
 plot(t,g)    

 axis([0 150 -12 15])

Answer 1

[KALYAN ACHARJYA]

% I didn't find any error during running the code, May be there is logical error

clc; 
  clear;
  close all;
  N=400;
  prompt=('Enter number of  terms to sum:');   
  i=input(prompt);   
  t=linspace(0,300,N+1);
  f=10*cos(50*t);
  g=zeros(1,N+1);
  for n=1:i
     g = g + ((-1)^n * (2500^n) * t.^(2*n)/(2*factorial(n)));
  end
  hold on
  plot(t,g)    
  axis([0 150 -12 15])

[KALYAN ACHARJYA]

t is having only two points 0,300

[aa bb]

it does not plot the the first term, sum of first 2 , sum of first 3 , etc... I am not sure where am I going wrong with the loop

[KALYAN ACHARJYA]

the sum of the first 3

[aa bb]

I want it to plot the sum of 1, then 2, then 3 with respect to the x axis. I believe right now it just sums all the terms in one go and shows just a line instead of a curve of some sort.