(;GM[1]FF[4]SZ[19]
GN[If White connects, Black makes an eye in sente]
PC[http://senseis.xmp.net/?HikaruProblem1/Solution]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?HikaruProblem1/Solution

If White connects, Black makes an eye in sente]
PL[B]

AB[db][dc][bd][cd][ce][de][ee][bf][cf][cg][dg][cl][dl][fl]
AW[cb][bc][cc][ec][ad][dd][ed][gd][be][fe][ff][bh][dh][eh][ci][ej][gj][ck][fk][bl]

;B[ab]C[B1]MN[1]
;W[ac]C[W2]MN[2]
;B[ae]C[B3]MN[3]
;W[eb]C[W4]MN[4]
;B[ef]C[B5]MN[5]

;
)
