Problem diagram.
White plays.

Analysis:
   Myron Souris

Solution follows    (or click here to download SGF)

Correct.
Black has 5 liberties while White only has 4. How can White save his stones?! If White had to rely only on liberties, White would lose the semeai by 1 move.

But White's saving tesuji at 1 threatens to connect out along the top edge! Through 7, White has "lost" the semeai with Black's 4 stones, but has connected out instead.

Although this problem is simple, if you're not paying attention in a game, the connection sequence is easy to miss!

Black variation.
Cutting White off with Black 4 doesn't work either, because Black reduces his internal liberties. Through 9, Black loses the semeai by 1 move.

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