(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play]
C[Just play through the moves to move 20 which is the problem position. These do not represent a game sequence!]
;B[pr]
;W[qr]
;B[ps]
;W[rr]
;B[qq]
;W[pq]
;B[rq]
;W[pp]
;B[rp]
;W[qp]
;B[ro]
;W[sq]
;B[oq]
;W[pn]
;B[op]
;W[qn]
;B[oo]
;W[rn]
;B[nr]
;W[sn]C[This is the problem position. Black to play.]
)
