(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
AW[cp][dp][ep][ar][br][cr][er][fr]AB[bo][co][do][eo][bp][fp][gp][aq][bq][fq][gr][gs]C[This is the problem position. Status?]
(;B[]C[If white plays to try and live where should he go?]
(;W[fs]C[This would look normal, but...]
;B[dr]C[There are liberty problems when black wedges in here.]
(;W[ds]
;B[dq]
;W[cq]
;B[eq])
(;W[eq]
;B[cq])
(;W[dq]
;B[ds]
;W[cs]
;B[eq]
;W[es]
;B[dr]
;W[ds]
;B[cq]))
(;W[dr]C[This appears to be a better way to live as it stops
the wedge.]
(;B[fs]
;W[es])
(;B[bs]
;W[fs]
;B[cs]
;W[ds]))
(;W[bs]
;B[dr]C[Now the wedge doesn't work]
;W[cq]
;B[es]
;W[ds]
(;B[fs]
;W[dq]
;B[eq]
;W[dr])
(;B[cs]
;W[dq]
;B[fs]
;W[ds]
;B[eq]
;W[dr]))
(;W[cq]C[This seems to work also]
(;B[eq]
(;W[dr]
;B[fs]
;W[es])
(;W[dq]
;B[es]
;W[ds]
;B[fs]
;W[bs]
;B[dr]
;W[er]C[This way lives at a small cost]))
(;B[es]
;W[fs]
;B[dr]
;W[ds]
;B[eq]
;W[dq]))
(;W[eq]C[And this works.]
(;B[cq]
;W[dr]
;B[fs]
;W[es])
(;B[es]
;W[fs]
;B[dr]
;W[ds]
;B[cq]
;W[dq])
(;B[fs]
;W[es]
;B[cq]
;W[dq])))
(;B[eq]C[If black plays first  and tries this...]
;W[dr]
;B[fs]
;W[es]C[White can live easily.])
(;B[dr]
;W[dq]
;B[ds]
;W[es]
(;B[eq]
;W[cq]
;B[cs]
;W[bs])
(;B[cq]
;W[cs]
;B[dr]
;W[eq]C[The extra liberty allows white to live after the wedge.]))
(;B[fs]
(;W[es]
;B[bs]C[Black can try and stop the eyes with here]
;W[cs]
(;B[eq]
(;W[dq]
;B[dr]
;W[ds]
;B[cq]C[This way dies.])
(;W[dr]C[But white can just play here]))
(;B[dr]C[But the wedge still kills]))
(;W[bs]
(;B[es]
;W[ds]
;B[eq]
;W[dq]C[This way white lives])
(;B[dr]C[But the wedge kills again]))
(;W[eq]
;B[es]
;W[ds]
;B[cq]
(;W[dr]
;B[bs])
(;W[bs]
;B[dr]))
(;W[cq]
;B[eq]
(;W[es]
;B[dr])
(;W[bs]
;B[dr])
(;W[dr]
;B[es]
;W[ds]
;B[bs]))
(;W[ds]
;B[bs]
;W[eq]
;B[cq]
;W[dq]
;B[es]))
(;B[bs]C[This move also kills, so white should play first to live
if they want to keep the group. 
]
(;W[cs]
;B[dr]C[And the wedge is the tesuji again])
(;W[cq]
;B[eq]
;W[dr]
(;B[cs]C[This is wrong]
;W[fs]
;B[ds])
(;B[fs]
;W[es]
;B[cs]C[This is dead again.]))
(;W[fs]
;B[dr]C[And again the wedge.]
;W[dq]
;B[ds]
;W[cs]
;B[eq]
;W[es]
;B[dr]
;W[ds]
;B[cq])))
