How would I go about modifying this code so that it will bin a set of 4 elements?

I have this following code where the is a pair of [ic(k), ic(k+1)]. Is there any way to modify it so that you can bin [[ic(k), ic(k+1), ic(k+2), ic(k+3)] instead? I have been playing with it but I keep getting errors, or a 4D matrix. Not what I want. Thanks in advance.

d = [3 3 4 4 4 5 6 5 5 4];
[c, ~, ic] = unique(d); 
N = numel(c); 
p = zeros(N, N); 
for k = 1:(numel(d) - 1)
  p(ic(k), ic(k + 1)) = p(ic(k), ic(k + 1)) + 1;
end
p = bsxfun(@rdivide, p, sum(p, 2));

[Walter Roberson]

Please show the desired output array (before the bsxfun)

[Walter Roberson]

Duplicated by later http://uk.mathworks.com/matlabcentral/answers/231397-transition-matrix-that-compares-two-elements-to-the-next-two-elements