(;GM[1]FF[4]SZ[19]
GN[black loses, if he wants to avoid the ko]
PC[http://senseis.xmp.net/?RTGProblem28/Attempts]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?RTGProblem28/Attempts

black loses, if he wants to avoid the ko]
PL[B]

AB[cp][dp][cq][eq][fq][iq][ar][cr][fr]
AW[fn][bo][co][do][ep][fp][dq][gq][dr][bs][ds][fs]

;B[gr]C[B1]MN[1]
;W[hr]C[W2]MN[2]
;B[hq]C[B3]MN[3]
;W[gp]C[W4]MN[4]
;B[ir]C[B5]MN[5]
;W[cs]C[W6]MN[6]
;B[br]C[B7]MN[7]
;W[bp]C[W8]MN[8]
;B[as]C[B9]MN[9]
;W[bq]C[W10]MN[10]

;
)
