(;GM[1]FF[4]SZ[19]
GN[Main line; B6 at W1]
PC[https://senseis.xmp.net/?GokyoShumyoSection5Problem21/Solution]AP[GoWiki:2009]
DT[2022-12-27]
C[Diagram from https://senseis.xmp.net/?GokyoShumyoSection5Problem21/Solution

Main line; B6 at W1]
PL[W]

AB[cb][fb][cc][dc][ec][gc][hc][bd][be][cf]
AW[ba][bb][bc][fc][cd][dd][ed][fd]

;W[eb]C[W1]MN[1]
;B[ea]C[B2]MN[2]
;W[ca]C[W3]MN[3]
;B[db]C[B4]MN[4]
;W[da]C[W5]MN[5]
;B[eb]C[B6]MN[6]
;W[gb]C[W7]MN[7]

;
)
