MATLAB: Array of U1 V1 U2 V2 U3 V3

symbolic array

Hi, as the title says, I need a symbolic array of U1 V1 U2 V2 U3 V3 .. Etc.
Number_of_elements = 100
UV = zeros(2*Number_of_elements,2)
for i = 1:Number_of_elements+1
U = sym('U',[i 1]);
V = sym('V',[i 1]);
UV(i,:) = [U(i), V(i)]
end
UV = UV(:)
I tried this, but then the following error occurs: Unable to convert expression into double array.
Does anyone see a good way to fix this?