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A087145
Number of distinct disconnected simple symmetric graphs on n nodes.
2
0, 1, 1, 2, 1, 3, 1, 4, 2, 4, 1, 9, 1, 4, 4, 9, 1, 11, 1, 14, 4, 4, 1, 25, 3, 6, 6, 14, 1, 27, 1
OFFSET
1,4
LINKS
Eric Weisstein's World of Mathematics, Symmetric Graph
FORMULA
a(n) = Sum{d|n, d<n} A133181(d). - Charlie Neder, Apr 24 2019
CROSSREFS
Cf. A133181 (number of connected symmetric graphs).
Cf. A286931 (number of not necessarily connected symmetric graphs).
Sequence in context: A338899 A362071 A194943 * A117172 A029207 A111902
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Aug 19 2003
EXTENSIONS
Corrected and extended by David Wasserman, Feb 14 2006
a(12)-a(31) from Charlie Neder, Apr 24 2019
STATUS
approved