

A048192


Number of connected chordal graphs on n vertices.


13



1, 1, 2, 5, 15, 58, 272, 1614, 11911, 109539, 1247691, 17566431, 305310547, 6558690953, 174688164414
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OFFSET

1,3


LINKS

Table of n, a(n) for n=1..15.
F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version 6e0a59d
B. D. McKay, Chordal graphs
Eric Weisstein's World of Mathematics, Chordal Graph
Eric Weisstein's World of Mathematics, Connected Graph


FORMULA

a(n) = A048193(n)  A287427(n).  Eric W. Weisstein, May 25 2017
Inverse Euler transform of A048193.  Andrew Howroyd, Nov 03 2017


CROSSREFS

Cf. A048193 (notnecessarily connected chordal graphs).
Cf. A287427 (disconnected chordal graphs).
Cf. A048194.
Sequence in context: A005976 A187981 A334155 * A078792 A208808 A266682
Adjacent sequences: A048189 A048190 A048191 * A048193 A048194 A048195


KEYWORD

nonn,nice,more


AUTHOR

Gordon F. Royle


EXTENSIONS

a(12) added by Gordon F. Royle, Aug 05 2008
a(13) and a(14) added using tinygraph by Falk Hüffner, Jan 15 2016
a(15) added by Brendan McKay, Jan 07 2019


STATUS

approved



