A048192 Number of connected chordal graphs on n vertices.

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

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

Tim Kemp, An algorithmic approach to a conjecture of Chvátal on toughness and hamiltonicity of graphs, M. Sc. Thesis, University of Twente (Netherlands, 2020).

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 (not-necessarily connected chordal graphs).

Cf. A287427 (disconnected chordal graphs).

Cf. A048194.

Sequence in context: A187981 A334155 A348365 * 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