I'm sure this is too simple, but at a quick glance...
EDIT - couldn't sleep
.do_again
n=n+1
For i=1 To 9
x=x+1
y=y+n
diag_check= temp_array(x,y)
Next
If n < 9 Then Goto do_again
EDIT - couldn't sleep
.do_again
n=n+1
For i=1 To 9
x=x+1
y=y+n
diag_check= temp_array(x,y)
Next
If n < 9 Then Goto do_again