I have redone the calcs and still doesn't work.
If we want to get the E12 it has a 10% tolerance
From the formula we get 1.78 rounded to 1.8 and the previous one was 1.5.
Now we search for overlapping:
1.51.1=1.65 <- 1.5 plus the 10%
1.80.9=1.62 <- 1.8 less the 10%
They overlap but, theorically, they are valid...
Any ideas?