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Search: a185959 -id:a185959
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Number of vertex-transitive graphs with n nodes.
(Formerly M0302)
+10
10
1, 2, 2, 4, 3, 8, 4, 14, 9, 22, 8, 74, 14, 56, 48, 286, 36, 380, 60, 1214, 240, 816, 188, 15506, 464, 4236, 1434, 25850, 1182, 46308, 2192, 677402, 6768, 132580, 11150, 1963202, 14602, 814216, 48462, 13104170, 52488, 9462226, 99880, 39134640, 399420, 34333800, 364724
OFFSET
1,2
REFERENCES
CRC Handbook of Combinatorial Designs, 1996, p. 649.
Brendan McKay, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Nino Bašić, Martin Knor, and Riste Škrekovski, On regular graphs with Šoltés vertices, arXiv:2303.11996 [math.CO], 2023.
Derek Holt and Gordon Royle, A Census of Small Transitive Groups and Vertex-Transitive Graphs, arXiv:1811.09015 [math.CO], 2018.
B. D. McKay and G. F. Royle, The transitive graphs with at most 26 vertices, Ars Combin. 30 (1990), 161-176. (Annotated scanned copy)
Brendan D. McKay, Gordon F. Royle, The transitive graphs with at most 26 vertices, Ars Combin. 30 (1990), 161-176.
Eric Weisstein's World of Mathematics, Vertex-Transitive Graph
Eric Weisstein's World of Mathematics, Cayley Graph
FORMULA
Inverse Moebius transform of A006800. - Andrew Howroyd, Sep 18 2018
CROSSREFS
Row sums of A319367.
KEYWORD
nonn,nice,hard
EXTENSIONS
More terms from Vladeta Jovovic, Jun 30 2007
a(32)-a(47) from Danny Rorabaugh, Nov 26 2018
STATUS
approved
Number of n-node vertex-transitive graphs which are not Cayley graphs.
(Formerly M0009)
+10
6
2, 0, 0, 0, 0, 4, 8, 0, 4, 0, 82, 0, 0, 0, 112, 0, 132, 0, 66, 0, 1124, 0, 18170, 0, 920, 6, 4162, 0, 0, 0, 48266, 0, 242, 0, 96, 294, 0, 0
OFFSET
10,1
REFERENCES
McKay, Brendan D.; Royle, Gordon F.; The transitive graphs with at most 26 vertices. Ars Combin. 30 (1990), 161-176.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Brendan D. McKay, Cheryl E. Praeger, Vertex-transitive graphs which are not Cayley graphs, I. J. Austral. Math. Soc. Ser. A 56 (1994), no. 1, 53-63.
Eric Weisstein's World of Mathematics, Noncayley Graph
FORMULA
a(n) = A006799(n) - A185959(n). - Andrew Howroyd, Nov 27 2018
CROSSREFS
KEYWORD
nonn,more
EXTENSIONS
More terms from Vladeta Jovovic, Jun 30 2007
a(32)-a(47) from Andrew Howroyd, Nov 27 2018
Duplicate a(32) removed by Andrew Howroyd, Sep 05 2019
STATUS
approved
Triangle read by rows: T(n,k) is the number of Cayley graphs with n nodes and valency k, (0 <= k < n).
+10
4
1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 2, 2, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 2, 3, 3, 2, 1, 1, 1, 0, 2, 0, 3, 0, 2, 0, 1, 1, 1, 2, 2, 4, 4, 2, 2, 1, 1, 1, 0, 1, 0, 2, 0, 2, 0, 1, 0, 1, 1, 1, 4, 7, 11, 13, 13, 11, 7, 4, 1, 1, 1, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 1
OFFSET
1,18
COMMENTS
First differs from A319367 in row 10.
LINKS
Gordon Royle, Transitive Graphs
Eric Weisstein's World of Mathematics, Cayley Graph
Wikipedia, Cayley graph
EXAMPLE
Triangle begins, n >= 1, 0 <= k < n:
1;
1, 1;
1, 0, 1;
1, 1, 1, 1;
1, 0, 1, 0, 1;
1, 1, 2, 2, 1, 1;
1, 0, 1, 0, 1, 0, 1;
1, 1, 2, 3, 3, 2, 1, 1;
1, 0, 2, 0, 3, 0, 2, 0, 1;
1, 1, 2, 2, 4, 4, 2, 2, 1, 1;
1, 0, 1, 0, 2, 0, 2, 0, 1, 0, 1;
1, 1, 4, 7, 11, 13, 13, 11, 7, 4, 1, 1;
1, 0, 1, 0, 3, 0, 4, 0, 3, 0, 1, 0, 1;
1, 1, 2, 3, 6, 6, 9, 9, 6, 6, 3, 2, 1, 1;
1, 0, 3, 0, 7, 0, 11, 0, 11, 0, 7, 0, 3, 0, 1;
1, 1, 3, 7, 15, 26, 39, 47, 47, 39, 26, 15, 7, 3, 1, 1;
1, 0, 1, 0, 4, 0, 7, 0, 10, 0, 7, 0, 4, 0, 1, 0, 1;
1, 1, 4, 7, 16, 23, 38, 45, 53, 53, 45, 38, 23, 16, 7, 4, 1, 1;
...
CROSSREFS
Column k=3 is aerated A319374.
Row sums are A185959.
KEYWORD
nonn,tabl
AUTHOR
Andrew Howroyd, Sep 17 2018
STATUS
approved
Number of 2n-vertex connected cubic vertex-transitive graphs which are Cayley graphs.
+10
2
1, 2, 2, 2, 4, 3, 4, 5, 5, 3, 11, 4, 5, 7, 10, 4, 12, 5, 10, 10, 7, 5, 32, 8, 9, 13, 13, 6, 30, 7, 26, 11, 11, 11, 36, 8, 11, 14, 29, 8, 27, 9, 16, 18, 13, 9, 90, 13, 23, 15, 20, 10, 41, 19, 35, 18, 17, 11, 100, 12, 17, 26, 82, 17, 35, 13
OFFSET
2,2
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 2..640, based on the work of Primož Potočnik, Pablo Spiga and Gabriel Verret
Primož Potočnik, Pablo Spiga and Gabriel Verret, A census of small connected cubic vertex-transitive graphs (see the sub-page Table.html)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 19 2014
STATUS
approved
Numbers k such that every vertex-transitive graph of order k is a Cayley-graph.
+10
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 17, 19, 21, 22, 23, 25, 27, 29, 31, 33, 37, 38, 39, 41, 43, 46, 47, 49, 53, 55, 59, 61, 62, 67, 69, 71, 73, 79, 83, 86, 87, 89, 93, 94, 95, 97, 101, 103, 107, 109, 113, 115, 118, 121, 123, 125, 127, 129, 131, 133, 134, 137, 139
OFFSET
1,2
COMMENTS
Numbers k for which A185959(k) = A006799(k).
Numbers k for which A006792(k) = 0.
In the Farrokhi reference, a Cayley number is a number k such that all vertex transitive graphs of order k are Cayley graphs.
LINKS
PROG
(GAP) # See M. Farrokhi Github repository for a GAP program.
CROSSREFS
KEYWORD
nonn
AUTHOR
M. Farrokhi D. G., Dec 26 2019
STATUS
approved
Numbers k such that there exists a non-Cayley vertex-transitive graph of order k.
+10
2
10, 15, 16, 18, 20, 24, 26, 28, 30, 32, 34, 35, 36, 40, 42, 44, 45, 48, 50, 51, 52, 54, 56, 57, 58, 60, 63, 64, 65, 66, 68, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 88, 90, 91, 92, 96, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 112, 114, 116, 117, 119, 120, 122, 124
OFFSET
1,1
COMMENTS
Numbers k for which A185959(k) < A006799(k).
Numbers k for which A006792(k) <> 0.
In the Farrokhi reference, a Cayley number is a number k such that all vertex transitive graphs of order k are Cayley graphs.
CROSSREFS
KEYWORD
nonn
AUTHOR
M. Farrokhi D. G., Dec 26 2019
STATUS
approved
Number of connected Cayley graphs on n nodes.
+10
0
1, 1, 1, 2, 2, 5, 3, 10, 7, 16, 7, 64, 13, 51, 40, 264, 35, 361, 59, 1110, 235, 807, 187, 15310, 461, 4089, 1425, 25726, 1181, 45118, 2191
OFFSET
1,4
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
M. Farrokhi D. G., Sep 24 2019
STATUS
approved

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