Inside the loop in the first instruction Vn(:,i) is 5x1 but T is 5x5. Matlab now (starting in 2016, I guess) implicitly expands Vn(:,i) to fit T, but the result of this expansion is a 5x5 matrix that you want to save in Vn(:,i+1) that is 5x1. Here comes the error. What do you want to do (with paper and pencil)?
Btw: I guess the initialization ov Vn should be zeros(5,95).