(;AW[aq]AW[bq]AW[cq]AW[dq]AW[er]AW[ds]AB[ap]AB[bp]AB[cp]AB[dp]AB[eq]AB[fr]AB[fs]AB[fq]AB[ep]C[In problem 6276 White could get a life in seki; but not here. Kill!]AP[goproblems]
(;B[bs]
(;W[br]
(;B[as]
(;W[cs]
(;B[dr]C[RIGHT])
(;B[es];W[dr])
(;B[cr];W[dr]))
(;W[dr];B[cs]C[Bent four in the corner. White is dead.RIGHT])
(;W[ar]
(;B[es];W[dr]
(;B[cs]C[RIGHT])
(;B[cr];W[cs]))
(;B[dr]
(;W[cr];B[es]C[RIGHT])
(;W[cs]
(;B[es]C[RIGHT])
(;B[bs]
(;W[as];B[es]C[RIGHT])
(;W[cr];B[es]C[RIGHT]))
(;B[as];W[es])))
(;B[cr];W[dr])
(;B[cs];W[cr]
(;B[es];W[bs])
(;B[bs];W[es])
(;B[cs];W[bs])
(;B[as];W[es])))
(;W[es]
(;B[cs];W[dr]C[Bent 4 in the corner, White is dead (by law). Black could physically remove White at the end of the game (when the last ko treats have been removed) by playing A2.RIGHT]MA[ar];B[ar]C[RIGHT];W[cr]C[RIGHT];B[bs]C[RIGHT];W[as]C[RIGHT];B[ar]C[Ko, but we assume White has no threats.RIGHT])
(;B[cr];W[dr])
(;B[dr];W[cr])
(;B[ar];W[cs]))
(;W[cr]
(;B[es]C[RIGHT])
(;B[cs];W[ar]
(;B[es];W[bs])
(;B[bs];W[es])
(;B[cs];W[bs])
(;B[as];W[es]))
(;B[ar];W[es])))
(;B[cs]
(;W[as]
(;B[es];W[cr])
(;B[ar]C[Ko for life. If Black wins, Black can end the ko by playing E1 or D2.]MA[es]MA[dr])
(;B[dr];W[cr])
(;B[cr];W[dr]))
(;W[cr]
(;B[es];W[as])
(;B[as];W[ar])
(;B[ar];W[as])))
(;B[es];W[cs]
(;B[dr];W[as])
(;B[as];W[dr])
(;B[cr];W[dr])
(;B[ar];W[as]))
(;B[dr]
(;W[as]
(;B[ar];W[cr]
(;B[es];W[as]C[Ko, white takes first.]MA[ar])
(;B[as];W[es])
(;B[cs];W[as]))
(;B[es];W[cs])
(;B[cr];W[cs])
(;B[cs];W[cr]))
(;W[cr]C[White should have played C1 here as that allows White to get a ko where White takes first.]
(;B[es];W[as]
(;B[ar]C[Ko, Black takes first.]MA[as])
(;B[dr];W[cs]))
(;B[ar];W[es])
(;B[as];W[es])
(;B[cs];W[as])))
(;B[cr];W[dr])
(;B[ar];W[cs]
(;B[dr];W[cr])
(;B[cr];W[dr])
(;B[es];W[as])))
(;W[es];B[cs];W[dr];B[ar]C[RIGHT])
(;W[dr];B[br]C[RIGHT])
(;W[cr];B[es]C[RIGHT])
(;W[cs];B[br]
(;W[es];B[cr]C[RIGHT])
(;W[cr];B[es]C[RIGHT]))
(;W[as];B[br]C[RIGHT])
(;W[ar];B[es]C[RIGHT]))
(;B[es];W[bs]
(;B[dr];W[cr]
(;B[ar];W[er]C[Ko, White takes first.])
(;B[cs];W[ar])
(;B[er];W[ar])
(;B[br];W[ar])
(;B[as];W[ar]))
(;B[cr];W[dr])
(;B[cs];W[dr])
(;B[br];W[ar]
(;B[dr];W[cr])
(;B[cr];W[dr])
(;B[cs];W[cr]))
(;B[ar];W[cr]C[Black next at D2 would start a ko for the life of this group.]MA[dr]MA[er])
(;B[as];W[ar]))
(;B[br];W[bs]
(;B[ar];W[cr];B[es];W[as]C[Black next at D2 would start a ko for the life of this group.]MA[dr]MA[er])
(;B[cr];W[ar])
(;B[cs];W[cr])
(;B[es];W[ar]
(;B[dr];W[cr])
(;B[cr];W[dr])
(;B[cs];W[cr]))
(;B[dr];W[cr])
(;B[as];W[ar]))
(;B[cr];W[br]
(;B[bs];W[dr])
(;B[es];W[dr])
(;B[dr];W[cs])
(;B[cs];W[bs])
(;B[ar];W[bs])
(;B[as];W[bs]))
(;B[cs];W[bs])
(;B[dr];W[cr]
(;B[bs];W[br]
(;B[es];W[as]
(;B[ar]C[Ko, Black takes first.]MA[as])
(;B[dr];W[cs]))
(;B[ar];W[es])
(;B[as];W[es])
(;B[cs];W[as]))
(;B[es];W[bs]
(;B[dr];W[ar])
(;B[ar];W[dr])
(;B[br];W[dr])
(;B[as];W[dr]))
(;B[ar];W[es]
(;B[bs];W[br])
(;B[cs];W[bs])
(;B[br]MA[bs]C[White can either live with points at B1 or take sente; the best Black can get is a gote seki.]))
(;B[br];W[bs])
(;B[cs];W[bs])
(;B[as];W[es]))
(;B[ar];W[br]
(;B[dr];W[cr]
(;B[es];W[as])
(;B[bs];W[es])
(;B[as];W[es])
(;B[cs];W[bs]))
(;B[es];W[as]
(;B[dr];W[cs])
(;B[cr];W[dr])
(;B[cs];W[dr])
(;B[bs];W[cs]))
(;B[cs];W[bs])
(;B[cr];W[bs])
(;B[bs];W[cs]
(;B[dr];W[cr])
(;B[cr];W[dr])
(;B[es]))
(;B[as];W[bs]))
(;B[as];W[bs]))