I am going to add the complete solution here. Let’s analyse the first row:
3+4+9 = 123644
We can see that 3*4 =12 and 4*9=36, so the first 4 digits from the number from the left are coming from this observations.
If we add the two products we are going to receive 12+36 = 48, and if we subtract 4 from this sum, we are going to receive 48-4=44
Following this observation in the next rows we can see that 5+4+5 = 20 20 (20+20-4 = 36)
7+2+5 = 14 10 (14+10-2=22), but the number written was 141021, so here comes the calculation error!
The puzzle is archived here:
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