(;GM[1]FF[4]SZ[19]
GN[Black to move]
PC[https://senseis.xmp.net/?GokyoSeimyoVolume3Problem30/Solution]AP[GoWiki:2009]
DT[2023-02-15]
C[Diagram from https://senseis.xmp.net/?GokyoSeimyoVolume3Problem30/Solution

Black to move]
PL[B]

AB[ab][bb][db][cc][dd][de][df][dg][ch][ci][aj][cj][bk]
AW[ac][bc][cd][be][ce][cf][cg][bh][bi][bj]

;B[ag]C[B1]MN[1]
;W[bg]C[W2]MN[2]
;B[ae]C[B3]MN[3]
;W[af]C[W4]MN[4]
;B[bf]C[B5]MN[5]
;W[ah]C[W6]MN[6]
;B[bd]C[B7]MN[7]

;
)
