@techreport{oai:ipsj.ixsq.nii.ac.jp:02009458,
 author = {平岡,和幸},
 issue = {6},
 month = {May},
 note = {どうぶつしょうぎにおける長周期千日手の存在を例示する。3×4の狭い盤面にも関わらず、この手順による同一局面の反復周期は8万手を超え、1手1秒でも一周23時間を要する。周期中の双方の着手はすべて、その局面での最善手（引き分けを保つ手）の一つであり、勝敗をくつがえす悪手は含まれない。このような長い千日手が生じ得る背景には、引き分け局面の遷移グラフが持つ目立った特徴として、約30万局面からなる巨大な強連結成分の存在がある。, We present an example demonstrating the existence of a long period repetition in Dobutsu Shogi, a variant of Japanese chess. Despite the small 3 × 4 board, the repetition cycle of identical positions generated by this sequence exceeds 80,000 plies, requiring 23 hours to complete a full cycle even at a rate of one ply per second. Throughout the cycle, every move by both players is one of the optimal moves available in the given position, i.e., a move that preserves the draw; no move that would alter the game-theoretic outcome is involved. A key structural factor underlying the possibility of such a long repetition is the existence of a giant strongly connected component, consisting of roughly 300,000 positions, in the transition graph of drawn positions.},
 title = {どうぶつしょうぎにおける周期8万手超の千日手},
 year = {2026}
}