2
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$$ six=two
$$ -.a.....
$$ -.......
$$ -...OOOO
$$ -4....XO
$$ -1OOOOOX
$$ -XOXXO.X
$$ -2X5.XX.
$$ -3......
$$ --------
White territory around a is safe
move 2 and 4 can be swapped for identical result.
Most moves have a name (at least in Chinese) I believe 2 would be called 破 (pò) = break (n...