Unexpected result calculating the determinant of a singular matrix (42S)

[Werner]

Ah yes indeed, you are right. So it is not impossible to have a 7x7 with integer elements < 100 and a condition number > 1e15, so that the cheat would not work.
Here's a 2x2 for which it fails:

Code:

[[ 49'999'999 49'999'998 ]
 [ 50'000'000 49'999'999 ]]

Cheers, Werner