(;GM[1]FF[4]SZ[19]
GN[White has to answer around 2 to prevent Black's escape]
PC[http://senseis.xmp.net/?BQM578/Attempt]AP[GoWiki:2009]
DT[2013-04-23]
C[Diagram from http://senseis.xmp.net/?BQM578/Attempt

White has to answer around 2 to prevent Black's escape]
PL[B]

AB[aa][ba][ca][ga][cb][db][gb][fc][gc][ed][be][ce][de]
AW[ea][fa][ab][eb][fb][ac][cc][dc]

;B[bb]C[B1]MN[1]
;W[bc]C[W2]MN[2]
;B[ec]C[B3]MN[3]
;W[da]C[W4]MN[4]

;
)
