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A129421 Number of isomorphism classes of connected 6-regular loopless multigraphs of order n. 9
0, 1, 1, 6, 15, 120, 933, 13303, 252207, 6450828, 205475039, 7936493756, 363639228194, 19476976825809, 1205115679461426, 85288127619421544, 6845235025444882069, 618411485467843477405, 62471139399366989007575, 7014991719815977343879171 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Initial terms computed using software at http://users.cecs.anu.edu.au/~bdm/nauty/

LINKS

Table of n, a(n) for n=1..20.

Brendan McKay and Adolfo Piperno, Nauty and Traces

FORMULA

Inverse Euler transform of A129422. - Andrew Howroyd, Mar 17 2020

PROG

(nauty/bash) geng -c -d1 ${n} -q | multig -r6 -u # Natan Arie Consigli, Jun 05 2017

CROSSREFS

Column k=6 of A328682.

Cf. A129422, A129432, A000421, A129417, A129419, A129423, A129425, A328682.

Sequence in context: A219771 A087137 A056317 * A013227 A013223 A219289

Adjacent sequences:  A129418 A129419 A129420 * A129422 A129423 A129424

KEYWORD

nonn

AUTHOR

Brendan McKay, Apr 15 2007

EXTENSIONS

a(1)=0 prepended and a(14)-a(20) from Andrew Howroyd, Mar 17 2020

STATUS

approved

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Last modified August 12 08:40 EDT 2022. Contains 356067 sequences. (Running on oeis4.)