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Number of connected graphs of odd girth at least 7 with n vertices.
1

%I #13 Jun 12 2021 02:37:47

%S 1,1,1,3,5,17,45,184,748,4143,26532,221032,2326853,32202266,589436301,

%T 14459238676,477812658943

%N Number of connected graphs of odd girth at least 7 with n vertices.

%C The odd girth of a graph is the length of a shortest cycle of odd length. Thus, these are the connected graphs that do not have a triangle or C_5 as induced subgraph. - _Falk Hüffner_, Jan 15 2016

%C The bipartite graphs (which have no odd cycles) are included.

%H F. Hüffner, <a href="https://github.com/falk-hueffner/tinygraph">tinygraph</a>, software for generating integer sequences based on graph properties, version ece94ef.

%Y Cf. A005142, A024607.

%Y Inverse EULER transform of A345247.

%K nonn

%O 1,4

%A Friedrich Regen (friedrich.regen(AT)tu-ilmenau.de), Sep 20 2009

%E a(15) and a(16) added using tinygraph by _Falk Hüffner_, Jan 15 2016

%E a(17) added by _Brendan McKay_, Jun 12 2021