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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..31.

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: A211110 A200780 A194943 * A117172 A029207 A111902

Adjacent sequences:  A087142 A087143 A087144 * A087146 A087147 A087148

KEYWORD

nonn,more,changed

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

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Last modified April 25 16:59 EDT 2019. Contains 322461 sequences. (Running on oeis4.)