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 A079473 Number of prime graphs on n vertices (G is prime iff G has no module. Module are also called homogeneous sets). 0
 0, 0, 0, 1, 4, 26, 260, 4670, 145870, 8110356, 804203096 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS A set of vertices S is called a module if every vertex outside S either sees all vertices in S or none of them. S must be > 1 and < size of the graph. LINKS F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version 6e0a59d. EXAMPLE The smallest prime graph and only one on 4 vertices is the 4-path. The 4 graphs on 5 vertices are: P5, C5, House and Bull. CROSSREFS Sequence in context: A215266 A002465 A248668 * A145164 A113078 A177451 Adjacent sequences:  A079470 A079471 A079472 * A079474 A079475 A079476 KEYWORD more,nonn AUTHOR Jim Nastos, Jan 15 2003 EXTENSIONS a(10) and a(11) added using tinygraph by Falk Hüffner, Jan 15 2016 STATUS approved

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Last modified February 23 15:24 EST 2020. Contains 332167 sequences. (Running on oeis4.)