# Variations of Our Solution (Ib)

# KataGo's 2021 Solution

VAR (.3) (.5)

(Referenced by 58ar; 58bc; 58bd; 58bi; 58by; 58cr) : ( 58ap) White must | |

: : Giving atari from below, with a move at , would have the same effect. It's just a matter of a change in the order of moves. : | |

: However, this move will increase the susceptibility to errors in the following course of the game unnecessarily (and can be a genuine mistake; 58by), and so can be considered to be a technical mistake in the timing of moves. : : | |

: However, an exchange of liberty occupying moves of the Main Semeai is unnecessary at the moment, and so can be considered to be a technical mistake in the timing of moves. : ( He would gain two points in the Semeai Variation, if he defended in the left centre with first. : : : : ( He would gain two points in the Semeai Variation, if he defended in the left centre with first. : : Please note that this move loses one tempo in the Main Semeai - in principle - as it does : : Please note that this kikashi is effective, only if White is able to deny Black's left-hand group any eye in the left centre. : ( Black does not have a sure eye in the left centre yet, but would be able to answer with the atari of from the left here, due to White's missing atari at the nakade. He would reach the same final scores of the game as with the sequence below. | |

: ( This move was my first candidate for a potential mistake in this subvariation, as there are more valuable points remaining on the board. White's move prevents a Black push into her upper right corner, but which Black does not want to play so early anyway. Capturing with in the lower left corner instead, completing the endgame sequence at the bottom, would not affect the overall result of the game. | |

If Black now connects at , and White connects at , the local score is zero. Therefore, Black is able to capture White's single stone in the upper right with . Compared to a White connection at , he gained one point locally. Both sides lost two tempi each in the Main Semeai, so Black is still one over par with the Punishment Semeai Liberty Level. Please note that White cannot achieve the usual benefit of one point by playing the kikashi at (while keeping Black without any eye in the left centre) here. | |

If Black now captures two White stones with , and White captures one Black stone with , the local score will be two points for Black. In principle, she will use her sente to prevent a one-point-reduction of her territory in the upper right, e.g. with - so gaining one point. Additionally, White did not lose any further tempo in the Main Semeai, so Black still has one Main Semeai Liberty to spend. | |

If White (with her move ) captures at In principle, he will use his sente to destroy one point of White's territory in the upper right by capturing White's single stone with . Thereafter, Black is three over par with the Punishment Semeai Libery Level, so he will be able to destroy another three points of White's territory. Please note that White cannot achieve the usual benefit of one point by playing the kikashi at (while keeping Black without any eye in the left centre) here. | |

: ( Alternatively, he might consider connecting his stone in atari. The overall result of the game would not be affected, but Black would benefit by two points in the Semeai Variation. : : : Otherwise, she would lose her stones at the left after Black's atari at . A move at would be too late then, due to . : : | |

Black must not play any reduction.
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Capture Variation: Compared to the superordinate variation, ... - Black's cumulated gain in the upper left corner is two points.
- White's cumulated gain at the top is four points.
- White destroyed one point of Black's territory in the left centre.
In total, White gained three points.
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Semeai Variation: Compared to the superordinate variation, ... - Black's cumulated gain in the upper left corner is two points.
- White's cumulated gain at the top is four points.
- White destroyed one point of Black's territory in the left centre.
- Black captured an additional White stone in the left centre, so gaining two points.
In total, White gained one point.
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