Verifying boardgame mathematics with MATLAB
Discussion

You have three dice, which you can assume to hold three places for 1, 2, 3, 4, 5, 6 and the four operations +, -, *, / would hold the two in-between places, which are shown as square brackets and round brackets respectively as shown in this blueprint - [] () [] () [].

The total number of possible combinations would be 6*4*6*4*6 = 3456. Out of these, you need to find the valid ones based on flooring and values in the range [1 100].

Looking at your code, I don't think -x+y would be a valid one, because you can't just pre-append a operator. If that is to be allowed, why not multiplication operator too? Moreover -x essentially means -1*x, for which you are already using two operators - - and * and assuming one of y or z to be 1. For these reasons, I am guesstimating, -x+y to be an invalid one, unless it says in the instructions manual to be a valid one.

Again, x\y won't induce anything new, as we are already juggling through all values of 1 to 6 across all three places around the four operators, as shown in the blueprint earlier.

Code  

Considering all the assumptions and avoiding the "scandalous" cases, we would have this vectorized code -

%// Define possible values of x, y and z, denoting values from three dice
x = 1:6;
y = 1:6;
z = 1:6;

%// t1 would take care of x and y and the one operator in between
t1 = [bsxfun(@plus,x',y) ; bsxfun(@minus,x',y) ; bsxfun(@times,x,y') ; bsxfun(@rdivide,x,y')]

%// t2 would take care of x, y and z and the two operators in between
t2 = [bsxfun(@plus,t1(:),z) ; bsxfun(@minus,t1(:),z) ; bsxfun(@times,t1(:),z) ; bsxfun(@rdivide,t1(:),z)]

%// Get the valid ones based on flooring and limiting within the range [1 100]
t2 = t2(t2==floor(t2) &amp; t2&lt;=100 &amp; t2&gt;=1)
freq = tabulate(t2)


Output

freq =
    1.0000  151.0000    7.6186
    2.0000  157.0000    7.9213
    3.0000  146.0000    7.3663
    4.0000  148.0000    7.4672
    5.0000  130.0000    6.5590
    6.0000  150.0000    7.5681
    7.0000   94.0000    4.7427
    8.0000  106.0000    5.3481
    9.0000   87.0000    4.3895
   10.0000   89.0000    4.4904
   11.0000   53.0000    2.6741
   12.0000   91.0000    4.5913
   13.0000   35.0000    1.7659
   14.0000   37.0000    1.8668
   15.0000   46.0000    2.3209
   16.0000   36.0000    1.8163
   17.0000   14.0000    0.7064
   18.0000   41.0000    2.0686
   19.0000   10.0000    0.5045
   20.0000   34.0000    1.7154
   21.0000   16.0000    0.8073
   22.0000   10.0000    0.5045
   23.0000    7.0000    0.3532
   24.0000   42.0000    2.1191
   25.0000   16.0000    0.8073
   26.0000    7.0000    0.3532
   27.0000   10.0000    0.5045
   28.0000   11.0000    0.5550
   29.0000    5.0000    0.2523
   30.0000   33.0000    1.6650
   ......


Observation

freq percentage value for 26 [red colored] is 0.3532 that is slightly lower than for 25 [pink colored] which has 0.8073. Similarly, for 13 [red colored] it is 1.7659, that is again slightly lower than for 15 [looks like pink colored], which has 2.3209.

To confirm, you can create another column to the "tabulated" one and mark different weights for each number from 1 to 100 based on their colors. Then, see if such a pattern continues across the entire board. Good luck and hope this would make sense!