A324218 Number of connected n-regular loopless multigraphs on six unlabeled nodes.

0, 0, 1, 6, 19, 49, 120, 263, 571, 1149, 2259, 4218, 7679, 13437, 22952, 38013, 61580, 97309, 150838, 229045, 342048, 502066, 726318, 1035482, 1457677, 2026369, 2785873, 3788494, 5101847, 6805192, 8998964, 11799997, 15353938, 19829063, 25431994, 32400113, 41021075, 51623423

Offset: 0

Author

Natan Arie Consigli, Feb 25 2019

Keywords

• nonn

Comments

Multigraphs are loopless.

Terms computed using 'nauty and Traces' (see the link).

Links

• Brendan McKay and Adolfo Piperno, nauty and Traces

Crossrefs

Row n=6 of A328682.

Cf. A324221, A324217.

Programs

nauty

for ((n=0;n<50;n++)); do geng -c -d1 6 -q | multig -r${n} -u; done