How to utilize 'symsum' in this case?

I'm trying to write this in MATLAB code, but when I try to use 'symsum' here, it requires that term Y_j and t_i should be expressed in 'j' and 'i', but

in this case, these terms are arbitrary numbers. For this reason, I guess using loop(e.g: for, while...) should be better, but I have no idea of using it. Are there better techniques that I never thought of?

Answer 1

[Star Strider]

Try something like this —

syms i j t Y 
Eq = symsum(Y,j,2,5) * (symsum(t,i,1,j)^2 - symsum(t,i,1,j-1)^2)

Eq = 

.