cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A319492 Number of connected non-3-semi-transitively orientable graphs on n vertices.

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%I A319492 #10 Sep 28 2018 10:19:18
%S A319492 0,1,25,929,54953,4879508
%N A319492 Number of connected non-3-semi-transitively orientable graphs on n vertices.
%C A319492 A graph is k-semi-transitively orientable if it admits an acyclic orientation that avoids shortcuts of length k or less. The notion of a k-semi-transitive orientation refines that of a semi-transitive orientation, which is the case of k equal infinity. For n<9, the number of non-3-semi-transitively orientable graphs is precisely the number of non-semi-transitively orientable graphs, which in turn is the same as the number of non-word-representable graphs. For n=9, there are four 3-semi-transitively orientable graphs which are not semi-transitively orientable.
%H A319492 Ozgur Akgun, Ian P. Gent, Sergey Kitaev, Hans Zantema, <a href="https://arxiv.org/abs/1808.01215">Solving computational problems in the theory of word-representable graphs</a>, arXiv:1808.01215 [math.CO], 2018.
%e A319492 The wheel graph W_5 is the only connected graph on 6 vertices that is non-3-semi-transitively orientable.
%Y A319492 The first four terms are the same as the terms 5 - 8 in A290814.
%K A319492 nonn,more
%O A319492 5,3
%A A319492 _Sergey Kitaev_, Sep 20 2018