Geodesic
On amorphic $C$-algebras
Zapiski Nauchnykh Seminarov POMI, Combinatorics and graph theory. Part I, Tome 340 (2006), pp. 87-102 
I. N. Ponomarenko; A. Rahnamai Barghi. On amorphic $C$-algebras. Zapiski Nauchnykh Seminarov POMI, Combinatorics and graph theory. Part I, Tome 340 (2006), pp. 87-102. http://geodesic.mathdoc.fr/item/ZNSL_2006_340_a5/
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     title = {On amorphic $C$-algebras},
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     year = {2006},
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     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2006_340_a5/}
}
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Voir la notice du chapitre de livre provenant de la source Math-Net.Ru

An amorphic association scheme has the property that any of its fusion is also an association scheme. In this paper we generalize the property to be amorphic to an arbitrary $C$-algebra, and prove that any amorphic $C$-algebra is determined up to isomorphism by the multiset of its diagonal structure constants and an additional integer equal $\pm 1$. We show that any amorphic $C$-algebra with rational structure constants is the fusion of an amorphic homogeneous $C$-algebra. As a special case of our results we obtain the well-known Ivanov's characterization of intersection numbers of amorphic association schemes.

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