(;AW[rb]AW[rc]AW[pc]AW[oc]AW[ob]AW[na]AB[nb]AB[mb]AB[md]AB[od]AB[nd]AB[pd]AB[qd]AB[rd]AB[rf]AP[goproblems]
(;B[sc];W[sb]
(;B[pa]
(;W[oa]
(;B[qb];W[qc];B[ra]C[CHOICERIGHT])
(;B[ra];W[qb];B[qa];W[qc]C[Seki])
(;B[qc];W[qb]))
(;W[qc]
(;B[ra];W[qa]
(;B[qb]C[CHOICERIGHT])
(;B[oa];W[pb]))
(;B[qa];W[oa];B[ra]C[];W[qb]C[Seki.])
(;B[oa];W[qa]
(;B[ma];W[pb])
(;B[pb];W[qb]))
(;B[qb];W[ra];B[oa];W[qa])))
(;B[qc];W[qb];B[pa];W[oa])
(;B[qb];W[qc]
(;B[pa];W[ra];B[oa];W[qa])
(;B[ra];W[pa];B[qa]C[Gote seki.]))
(;B[ra];W[qb];B[pa];W[oa];B[qa];W[qc]C[Only seki]))
(;B[pa];W[qc]
(;B[sc];W[qa]
(;B[sb];W[pb])
(;B[pb];W[sb])
(;B[oa];W[pb]LB[oa:A]LB[sb:B]C[A and B are miai]))
(;B[oa];W[qa]
(;B[sc];W[pb])
(;B[ma];W[pb]))
(;B[ra];W[sc]
(;B[oa];W[qa]
(;B[qb];W[pb];B[ma];W[sa];B[sb];W[qa]C[White lives in double ko.])
(;B[ma];W[pb];B[qb];W[sa];B[sb];W[qa]C[White lives in double ko.]))
(;B[sa];W[oa]C[At least seki for white.]))
(;B[qa];W[oa]
(;B[ra];W[sc]C[White lives (May be black can get a seki by playing at A.]LB[sd:A])
(;B[sc];W[sb];B[ra];W[qb]C[Only seki])))
(;B[qc];W[qb]
(;B[pa];W[oa])
(;B[sc];W[pa]))
(;B[qa];W[ra]C[White has two eyes.])
(;B[ma];W[ra])
(;B[qb];W[qc]
(;B[sc];W[sb]
(;B[pa];W[ra];B[oa];W[qa])
(;B[ra];W[pa];B[qa]C[Gote seki for black.]))
(;B[pa];W[ra];B[oa];W[qa])
(;B[ra];W[pa]
(;B[qa];W[sc]C[At lest seki for white.])
(;B[sc];W[sb];B[qa]C[Gote seki.])))
(;B[sb];W[sc]))