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Caractéristiques des XVIII classes de systèmes. 



I. (2,) - («, >, M- 



II. G. 2') = (i, 2. 2). 



III. (2, G, G') = (1, a, 2). 



IV. (S, KO) = (i, a, 2). 



V. (ï\G0k) ^ (1, 2, 2). 



VF. (g, G', Ko) ^ (1, 2, 1). 



vu. ((CgCg%'g > ') - (1, a, ')• 



VIII. (2, G, ip.) = (1, 2, 2), 

 (O", >d.) = (2, 4, 4). 

 (O, ip) - (2, 4, 4), 



IX. (g, G', G*, ip.) = (1, a, 1), 

 (^"gTg", ul.) - (2, 4, 2), 



(gX>, ip) - (1, ^- >)• 



X. (kOgT&', 2p. ) = (1, 2, 2). 

 (kOG, G', ip., ni.) = (2, 4, 4), 

 (kOG, G', ad.) = (4, 4, 4), 

 (KOG, G', ip., IP ) = (2, 4, 2), 

 (KOG, G', 2P ) = (2, 2, 1). 



XI. (G, G', ap. ) = (1. a, 1), 

 (G, G', ip-, ni-) = (2, 4, a), 

 (G, G', ad.) (4, 8, 4), 

 (G, G', ip., iP ) - (1, a, 1). 

 (G, G', aP ) = (1,2, 1). 



XII. (KO, K'O', ap. ) = (1, a, a), 

 (KO, K'O', ap., k1.) -- (a, a, a), 

 (KO, K'O'. ad.) = (a, 4, 2), 

 (KO. K'O', ip.. il' 1 (a, a, a), 

 (KO. K'O', aP ) (2, a, 1). 



