(;AB[fb][ec][fc][gc][ed][dd][de][ce][cf][bf][cg][dg][dh][eh][ei][fi][fj][gd][hd][he][ie][hf][hg][hh][hi][hj][hk][hl][hm][hn][cs][es][dr][cq][dq][eq][fp][go][gn][fo][ep][bp][cp][dp][co][dn][em][fl][gl][fm][gm][en][fn][do][eo][ij][jj][kj][lj][mj][li][lh][lg][lf][le][ke][ld][mc][nb][oc][pd][qe][rf][qg][ph][oi][mi][md][nc][od][pe][qf][pg][oh][mk][nk][ok][pl][qm][rn][qo][pp][oq][nr][mq][lp][ko][jn][kn][ln][mn][ml][mm][lm][lo][mo][no][oo][po][qn][pn][nn][nm][om][on][pm][ol][nl][np][mp][op][nq]AW[er][fs][gr][fq][gp][ho][in][jm][km][ll][lk][kk][jk][ik][il][im][jo][kp][lq][mr][ns][or][pq][qp][ro][sn][rm][ql][pk][oj][nj][ni][nh][mh][mg][mf][me][ne][oe][nd][of][pf][og][pi][qh][rg][sf][re][qd][pc][ob][na][mb][lc][kd][je][if][ig][ih][ii][ji][ki][kh][kg][kf][jf][id][hc][gb][fa][eb][dc][cd][be][af][bg][ch][di][ej][fk][gk][gj][gi][gh][gg][gf][ge][fe][fd][ee][df][ef][eg][fh][el][dm][cn][bo][ap][bq][cr][ar][bs][an][bm][cl][dk][cj][bi][ah][ad][bc][cb][da][ha][ib][jc][kb][la][pa][qb][rc][sd][sh][ri][qj][rk][sl][sp][rq][qr][ps][ls][kr][jq][ip][hq]C[From "go-chelrubriek,  by Ger Hungerink in "Go - tijdschrift van de Nederlanse go-bond (the Dutch Go Association).  Vol 25/4.

In this problem, I believe that Ger was looking for the longest multistep ko -- 100 steps to return to the start position.]
;B[br];W[ds];B[aq];W[cr];B[ao];W[bq];B[bn];W[ap];B[cm];W[bo];B[dl];W[cn];B[ek]
;W[dm];B[dj];W[el];B[ci];W[ej];B[bh];W[di];B[ag];W[ch];B[ae];W[bg];B[bd];W[af]
;B[cc];W[be];B[db];W[cd];B[ea];W[dc];B[ga];W[eb];B[hb];W[fa];B[ic];W[gb];B[jd]
;W[hc];B[kc];W[id];B[lb];W[kd];B[ma];W[lc];B[oa];W[mb];B[pb];W[na];B[qc];W[ob]
;B[rd];W[pc];B[se];W[qd];B[sg];W[re];B[rh];W[sf];B[qi];W[rg];B[pj];W[qh];B[qk]
;W[pi];B[rl];W[pk];B[sm];W[ql];B[so];W[rm];B[rp];W[sn];B[qq];W[ro];B[pr];W[qp]
;B[os];W[pq];B[ms];W[or];B[lr];W[ns];B[kq];W[mr];B[jp];W[lq];B[io];W[kp];B[hp]
;W[jo];B[gq];W[ho];B[fr];W[gp];B[es];W[fq];B[cs];W[er])