{. ,

M. ?i-=-j and ?. {?1, , p.1

. Enfin, nous utilisons ces résultats pour démontrer que dans ces conditions, l'orbite de x pour l'action de Z 2 est incluse dans celle pour l

, Graphe étiqueté et connexité Nous allons associer un graphe G x à tout élément x de B(R) La correspondance matrice M x ? graphe G x sera bijective

, Graphe étiqueté associé à x ? B(R), action des mutations

, Definition 57. À toute matrice x ? B(R), nous associons un graphe étiqueté G x = (S, A)

S. and {. , } désigne l'ensemble des sommets pour i = j, (i, (M x ) ij , j) ? A ?? (M x ) ij = (x i

{. ,

M. ?i-=-j and ?. {?1, , p.1

, Notre objectif est de montrer que pour tout x ? BW (R)e, la matrice M x est une matrice de Gabrielov

. Nous-dirons-qu,

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