% getting familiar with the rand() function:
rand(1, 3)
rand(3, 1)
rand(2, 4)

% three times the same sequence of 10 random numbers:
n = 10;
for k = 1:3
    rand(1, n)
end

% serial correlation at lag 1:
n = 10000;
x = rand(n, 1);
r1 = corr(x(1:end-1), x(2:end));
fprintf('correlation between subsequent random numbers: %.3f\n', r1);