Under The Stones Problem 7

Here is my favourite. I particularly like how you can tell the solution is under the stones instantly, but it is still hard. PS: Correct play by white is quite hard too, so if you think you've solved it, make sure you didn't miss a tesuji. Oh, forgot to mention that ko is not good enough.

Black to move and live  

Happy solving :-) Corrin Lakeland

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