A361406 Number of bicolored connected cubic graphs on 2n unlabeled vertices with n vertices of each color.

1, 0, 1, 5, 63, 1052, 27336, 882321, 34455134, 1558650424, 80016369538, 4589908631503, 290839634055722, 20171917072658395, 1519875854413728667, 123616508830454828043, 10794216583730162449785, 1007179737486515827821590, 100007950522974604304016627, 10529173417583858651114779790, 1171605981584666223513790021758

Offset

0,4

Comments

Adjacent vertices may have the same color.

Links

Table of n, a(n) for n=0..20.

Example

a(1) = 1 since the only cubic graph on 4 vertices is the complete graph. The bicolored graphs are indistinguishable whichever 2 vertices are colored in the first color.

Crossrefs

Central coefficients of A321304.

Cf. A002851, A361407, A361408.

Sequence in context: A222376 A243218 A112788 * A355411 A334907 A218102

Adjacent sequences: A361403 A361404 A361405 * A361407 A361408 A361409

Keyword

nonn

Author

Andrew Howroyd, Mar 11 2023

Status

approved