Byusingthat formula. When i= j= 1, . When i= 1, j= 2, . When i= 1, j= 3, [tex]A_{12}= \frac{1}{1+ 6- 1}= \frac{1}{6}.

When i= 2, j= 1, . When i= 2, j= 2, . When i= 2, j= 3, .

When i= 3, j= 1, .

When i= 3, j= 2, .

When i= 3, j= 3, .

That is,

is the 3 by 3 matrix. Looks like there is a pretty simple pattern so you should be able to extend that to 5 by 5, 10 by 10, and 15 by 15.