(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[9]KM[0.00]
PW[hb-797-RAVE-50k]PB[AmiGoGtp]AW[aa][ba][ca][da][ea][fa][ga][ia][bb][eb][fb][gb][hb][bc][dc][ec][gc][dd][id][be][ce][de][he][df][ef][hf][if][eg][gg][hg][ig][eh][fh][gh][hh][ih][ii]AB[ab][cb][db][ib][ac][cc][fc][hc][ic][ad][bd][cd][ed][gd][hd][ae][ee][fe][ge][af][bf][cf][ff][gf][ag][cg][dg][fg][ah][bh][dh][ai][ci][di][ei][fi][gi][hi]C[Starting position, as caught in an infinite (playout) loop.

Black can't fill an eye (b1,b3,c2)
Black can't commit suicide (f6)

Black must take a ko, either H9 or J5]
;B[ie]C[White can't commit suicide (H9)
White can't retake the ko (J6)

White must play F6 and capture F7 (ko)]
;W[fd]C[Black can't commit suicide (J6)
Black can't retake the ko (F7)

Black must play H9 and capture J9 (ko)]
;B[ha]C[White can't commit suicide (F7)
White can't retake the ko (J9)

White must play J6 and capture J5 (ko)]
;W[id]C[Black can't commit suicide (J9)
Black can't retake the ko (J5)

Black must play F7 and capture F6 (ko)]
;B[fc]C[White can't commit suicide (J5)
White can't retake the ko (F6)

White must play J9 and capture H9 (ko)]
;W[ia]LB[ha:3][ia:6][fc:5][fd:2][id:4][ie:1]C[This matches the original board position, with only one move option after each move, the 6-move cycle continues as shown]
;B[ie]
;W[fd]
;B[ha]
;W[id]
;B[fc]
;W[ia]C[Another repeat of the starting position...]
;B[ie]
;W[fd]
;B[ha]
;W[id]
;B[fc]
;W[ia]C[...]
;B[ie]
;W[fd]
;B[ha]
;W[id]
;B[fc]
;W[ia]C[...]
;B[ie]
;W[fd]
;B[ha]
;W[id]
;B[fc]
;W[ia]C[That's enough...])
