(;AB[pr]AB[qr]AB[qq]AB[qp]AB[qo]AB[ro]AW[or]AW[nq]AW[pq]AW[pp]AW[po]AW[pn]AW[qn]AW[rn]AW[so]AW[sn]AB[sp]C[White to kill. Seki is insufficient. ]AP[goproblems]
(;W[sq];B[sr]
(;W[rp];B[rq]
(;W[sp];B[rs])
(;W[rs];B[sp]))
(;W[rr];B[rq])
(;W[rq];B[rr]))
(;W[sr]
(;B[rq]C[CHOICE]
(;W[sq];B[rr];W[rp]C[KoRIGHT])
(;W[rs];B[rr]))
(;B[rr]C[];W[sq];B[rq];W[rp]C[KoRIGHT])
(;B[ps]C[CHOICE]
(;W[sq];B[rp]
(;W[rs];B[rr]C[Seki])
(;W[rr];B[rs];W[os]C[Seki]))
(;W[rq];B[rr]
(;W[sq];B[rp];W[rs];B[ss];W[sr];B[sq])
(;W[rs];B[rp]))
(;W[rp];B[rq];W[sq];B[rr];W[rp]C[KoRIGHT])
(;W[rs];B[rr];W[sq];B[rp]C[Seki])
(;W[rr];B[rs]
(;W[ss];B[rq];W[qs];B[sq])
(;W[rq];B[rp];W[os]C[Seki])
(;W[sq];B[rp];W[os]C[Seki]))))
(;W[rs];B[sr])
(;W[ps];B[sr])
(;W[rq];B[sr])
(;W[rr];B[rq]))