@André Camargo - My following statement is based on my understanding that you want to have 3 cells (A1, A2, A3) linked to another cell B1. B1 shall have the value 0 when the cells A1, A2, A3 have the same value and B1 shall have the value 1 if at least one of the cells A1, A2, A3 has a different value.

I tried a different approach than @mariosv and did a test with LibO 3.6.5 and found that Calc reacts correct if the functions are used in the right way. Error messages are missing when the functions are not used as required in the syntax.

I set a1=1 a2=1 a3=1

First I tested the logical function AND and wrote in b1:

=AND(A1=A2,A2=A3)

whenever the values in a1, a2, a3 are the same b1 shows TRUE, which is correct

whenever there is at least one of the values of a1, a2, a3 is different from the others, b1 shows FALSE, which is correct again

Next I combined AND with IF and wrote in b2:

=IF (AND(A1=A2,A2=A3),0,1)

whenever the values in a1, a2, a3 are the same b2 shows 0, which is correct

whenever there is at least one of the values of a1, a2, a3 is different from the others, b2 shows 1, which is correct again.

Thus above IF function could solve your problems - if my understanding is correct.

However your IF function

=IF(B1347=B1348=B1349)

triggered thoughts that this cannot work because of the string

B1347=B1348=B1349

has a problem and the function IF is not completed according to its syntax.

My test is using in b3

=IF(A1=A2=A3)

which shows a wrong results. Exactly the opposite of what is should be. b3 shows FALSE whenever the values in a1, a2, a3 are the same, and TRUE whenever there is at least one of the values of a1, a2, a3 is different from the others.

IMHO, and as far as I understand the syntax of the IF function, an error message should appear indicating the formula is not completed and not show any value. Additionally the string "A1=A2=A3" should also lead to error message as a computer can in one action only compare two values. That is why there is the AND function.

I continued the test ... (more)

OP: @André Camargo