how to find the square of the number

i have a matrix x where x(:,3)=[ 2 3 4 5 6];

i want the output as y(:,1)=[ 6 16 40 96 ];

input and output should be column vectors. ignoring the first element of input. i want the input to be multiplied with the (row number)^i. where i=1:length(x-1)

the code i tried is below

y=[];
for i=1:(size(x)-1)
    y(i,1)= i^2*(x(2:length(x),3));
end

im getting the error as dimensions mistached, could u help me out

Answer 1

[per isakson]

This produces something that is close to the result you want

%%
x(:,3)=[2;3;4;5;6];
len = size(x,1);
y = nan( len-1, 1 );
for ii = 1:len-1
    y(ii,1)= ii^2*x(ii+1,3);
end

Obviously, I'm missing something in your description

[johnson saldanha]

thank you. it works fine