(;GM[1]FF[4]SZ[19]
GN[(White would then take the two step ko first by capturing B7)]
PC[http://senseis.xmp.net/?GokyoShumyoSection3Problem39/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?GokyoShumyoSection3Problem39/Attempts

(White would then take the two step ko first by capturing B7)]
PL[B]

AB[db][dc][ed][ce][de][ee]
AW[eb][cc][ec][gc][cd][dd]

;B[cb]C[B1]MN[1]
;W[bb]C[W2]MN[2]
;B[bc]C[B3]MN[3]
;W[bd]C[W4]MN[4]
;B[ba]C[B5]MN[5]
;W[ac]C[W6]MN[6]
;B[ab]C[B7]MN[7]

;
)
