ronk wrote:Carcul wrote:Here is a longer chain that also craks the puzzle:
[r2c3]=7=[r2c2]-7-[r7c2]-9-[r7c5]-5-[r7c4]-1-[r4c4]-7-[r4c3]-5-[r1c3]
-4-[r3c3]-8-[r2c3] => r2c3<>8.
Carcul
If I'm reading the above correctly, one starts on the left with r2c3<>7 ... and following the chain ends on the right with r2c3<>8 ... but how does the conclusion r2c3<>8 follow from that?
From the chain notation, the following proof can be listed:
r7c4=5 => r7c5=9 => r7c2=7 => r2c2<>7 => r2c3=7 => r2c3<>8
r7c4=1 => r4c3=5 => r1c3=4 => r3c3=8 => r2c3<>8
both imply r2c3<>8
