(;GM[1]FF[4]SZ[19]
GN[Black to play and connect underneath]
PC[https://senseis.xmp.net/?IgoHatsuyoRonProblem126/Solution]AP[GoWiki:2009]
DT[2023-02-03]
C[Diagram from https://senseis.xmp.net/?IgoHatsuyoRonProblem126/Solution

Black to play and connect underneath]
PL[B]

AB[ra][ob][qb][pc][od][oe][qg][rg][ni][oi][pi][qi]
AW[rb][qc][pd][qd][pf][mg][pg][nh][mi][ri][mj][ok][qk][rk]
LB[rd:a][re:b][rf:c]

;B[og]C[B1]MN[1]
;W[oh]C[W2]MN[2]
;B[ph]C[B3]MN[3]
;W[of]C[W4]MN[4]
;B[nf]C[B5]MN[5]
;W[ng]C[W6]MN[6]
;B[pe]C[B7]MN[7]
;W[qf]C[W8]MN[8]
;B[sd]C[B9]MN[9]

;LB[rd:a][re:b][rf:c]
)
