get rid of blue triangle

To remove the warning triangle, you'll need to fix the issue that is causing it. Click on the triangle to read the message it is a flag for. Without information regarding what it is warning of, it's difficult to offer a solution.

Regards,

Barry

Try this instead:

=INT((STRIPDURATION(A2−DATE(YEAR(A2−WEEKDAY(A2−1)+4),1,3))+WEEKDAY(DATE(YEAR(A2−WEEKDAY(A2−1)+4),1,3))+5)/7)

In Dutch:

=INTEGER((VERWIJDER.TIJDSDUUR(A2−DATUM(JAAR(A2−WEEKDAG(A2−1)+4);1;3))+WEEKDAG(DATUM(JAAR(A2−WEEKDAG(A2−1)+4);1;3))+5)/7)

When copy-pasting, be sure to scroll to the right to get the whole formula.

SG

Shouldn't be giving you a warning notice if you're using the WEEKNUM function in the right side cell.

Weeknum accepts a Date and Time value, ignores the time part, and returns a number value.

Unless your formula is more complex than this one, I see no reason for the warning triangle.

Regards,

Barry