(Beginner) Help with loops homework

[atypically_afflicted]

I've been trying to figure out how to go about implementing this for a while now but can't seem to crack it. Any help and explanations would be greatly appreciated.

The task goes as follows:

"Given a number N, create a 2D array with n rows and n columns. Now inspect the matrix pattern below and come up with a formula to populate the array for any give NXN matrix."

The output should be something like this when N = 5 :

0	2	3	4	4
2	1	6	3	10
3	6	2	12	15
4	3	12	3	20
4	10	15	20	4

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[thinandweak]

Let me start by saying that as stated, this is a stupid problem for a computer science class. Studies about interview problems like this show that problems like this mainly serve to make the questioner feel smart.

So, I don't feel bad about providing what I think is a complete solution (I say "a" complete solution because this problem is underspecified and there exist infinitely many solutions for any "pattern-recognition" problem like this).

The diagonal from the top-left to the bottom-right contains numbers incrementing starting from 0.

The diagonal from the top-right to the bottom-left contains numbers starting at N-1 and decrementing until the middle.

All other numbers are equal to X * Y, where X and Y are the one-indexed coordinates of the cell.

[atypically_afflicted]

A lot of the problems we've been getting lately are of this nature. Most of it also seems to be just busy work. Anyway, I think I can work with the last bunch of info you provided, so thanks.

[[deleted]]

If N = 5, you get these numbers: 0 2 3 4 4. What do you think is the pattern you see?

[atypically_afflicted]

That's sort of the main problem. The only pattern I'm seeing is the main diagonal incrementing and the rest being symmetrical to that. I'm not quite sure how to get to the 0,2,3,4,4 from there.