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Search: a006792 -id:a006792
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a(n) = A006792(n)/2.
+20
0
1, 0, 0, 0, 0, 2, 4, 0, 2, 0, 41, 0, 0, 0, 56, 0, 66, 0
OFFSET
10,6
KEYWORD
nonn
STATUS
approved
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 Cayley graphs on n nodes.
+10
7
1, 2, 2, 4, 3, 8, 4, 14, 9, 20, 8, 74, 14, 56, 44, 278, 36, 376, 60, 1132, 240, 816, 188, 15394, 464, 4104, 1434, 25784, 1182, 45184, 2192, 659232, 6768, 131660, 11144, 1959040, 14602, 814216, 48462, 13055904, 52488, 9461984, 99880, 39134544, 399126, 34333800, 364724
OFFSET
1,2
COMMENTS
First differs from A006799 at n = 10.
LINKS
Derek Holt and Gordon Royle, A Census of Small Transitive Groups and Vertex-Transitive Graphs, arXiv:1811.09015 [math.CO], 2018.
Eric Weisstein's World of Mathematics, Cayley Graph
FORMULA
a(n) = A006799(n) - A006792(n).
MATHEMATICA
A006792 = Join[Array[0&, 10], Cases[Import["https://oeis.org/A006792/b006792.txt", "Table"], {_, _}][[All, 2]]];
A006799 = Cases[Import["https://oeis.org/A006799/b006799.txt", "Table"], {_, _}][[All, 2]];
a[n_] := A006799[[n]] - A006792[[n+1]];
Array[a, 47] (* Jean-François Alcover, Sep 05 2019 *)
CROSSREFS
Row sums of A319372.
KEYWORD
nonn,hard
AUTHOR
Eric W. Weisstein, Feb 07 2011
EXTENSIONS
a(32)-a(47) from Danny Rorabaugh, Nov 26 2018
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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