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

0,4

Comments

Multigraphs are loopless.

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

Links

Table of n, a(n) for n=0..37.

Brendan McKay and Adolfo Piperno, nauty and Traces

Prog

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

Crossrefs

Row n=6 of A328682.

Cf. A324221, A324217.

Sequence in context: A073362 A095264 A269059 * A229731 A360951 A271904

Adjacent sequences: A324215 A324216 A324217 * A324219 A324220 A324221

Keyword

nonn

Author

Natan Arie Consigli, Feb 25 2019

Status

approved