(;GM[1]FF[4]SZ[19]
GN[Absolutely necessary]
PC[http://senseis.xmp.net/?ApproachOnTheOpenSideExceptions]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?ApproachOnTheOpenSideExceptions

Absolutely necessary]
PL[B]

AB[mb][nb][rb][dc][nc][oc][pc][rc][ed][qd][rd][oe][pe][qe][re][nf][qf][pg][ci][dp]
AW[lb][qb][mc][qc][gd][jd][md][nd][od][pd][ne][se][of][pf][rf][og][qg][oh][qh][pp]

;B[qn]C[B1]MN[1]
;W[qo]C[W2]MN[2]
;B[pn]C[B3]MN[3]
;W[np]C[W4]MN[4]
;B[pk]C[B5]MN[5]
;W[fq]C[W6]MN[6]
;B[dn]C[B7]MN[7]
;W[iq]C[W8]MN[8]

;
)
