Problem	4570
Created	2004-06-02
Source
Rating

Difficulty	7 dan
Average Solve Time	65 secs
User Attempts	157 / 1579
Solve Ratio Rating	3 dan
	rating history

Many thanks to Zenit, bass, tigre, blyx, romi,zinger and especially tails for their comments.
If there are any errors please comment.

(;AB[cd]AW[ec]AB[dc]AW[ed]AW[dd]AB[cb]AW[ce]AB[bd]AW[be]AW[df]AW[bc]AW[bg]AW[gc]AW[hb]AW[ib]AB[gf]AB[fg]AB[hf]C[]AP[goproblems] (;B[cc];W[bb] (;B[ad];W[eb]) (;B[ba];W[ab]) (;B[eb];W[ad] (;B[fb];W[ca]) (;B[ba];W[ac]) (;B[ac];W[ab]) (;B[ab];W[ac])) (;B[ac];W[ab] (;B[ba];W[ad]) (;B[ad];W[eb])) (;B[ab];W[ba] (;B[ac];W[eb];B[db];W[da]) (;B[eb];W[fb] (;B[da];W[fa] (;B[ac] (;W[ea] (;B[db];W[ae];B[ad]C[seki!RIGHT]) (;B[ad];W[db]) (;B[ca])) (;W[ae] (;B[ea];W[ad]C[It's not a seki as white can capture a17/a18 and connect out]) (;B[ad];W[ea]))) (;B[ea];W[ca]) (;B[ca];W[ea]) (;B[ad];W[ea])) (;B[ca];W[ea]) (;B[ac];W[ea] (;B[db];W[da]) (;B[da];W[db]C[Black cannot win this one])) (;B[ad];W[ea] (;B[db];W[da]) (;B[da];W[db])) (;B[ea];W[ca] (;B[da];W[ad];B[db];W[fa]) (;B[db];W[ad];B[ac];W[ae]) (;B[ac];W[fa] (;B[da];W[db]) (;B[db];W[ae];B[ad]C[seki!RIGHT])) (;B[ad];W[fa];B[db];W[ac]))) (;B[ad];W[eb]))) (;B[bb];W[ad] (;B[cc];W[ab] (;B[ac]C[Unfavourable ko for black.]) (;B[eb];W[ac] (;B[da];W[ba];B[fb];W[fa]) (;B[fb];W[da]) (;B[ba];W[da]))) (;B[eb];W[cc]) (;B[ab];W[cc]) (;B[ac];W[cc])) (;B[eb];W[cc];B[bb];W[ad]) (;B[ac];W[bb] (;B[ab];W[ba];B[cc];W[eb];B[db];W[da]) (;B[ba];W[ab]) (;B[cc];W[ab] (;B[ba];W[ad]) (;B[ad];W[eb]))))