Mod and If Problem [Mathematica]

I have problem with the following code :(

Code:

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Table[If[Mod[i, 3] <= 1 Or Mod[j, 3] <= 1, 29/512, 23/256], {i, 0,
  3}, {j, 0, 3}]

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How to correct it?

By the way, I need to simplify

Code:

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-9+\frac{69 (69)^{1/4}}{256}

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by Mathematica to get the output .

Thanks. ;)

For the first one, I find out that

Code:

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Table[If[(Mod[i, 3] <= 1) && (Mod[j, 3] <= 1), 29/512, 23/256], {i, 0,
  2}, {j, 0, 2}]

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works good.

For the second one

Code:

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N[-9+\frac{69 (69)^{1/4}}{256}]

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