A185293 Number of disconnected 9-regular graphs with 2n nodes.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 9, 88238, 113315027550, 281342192047999912, 1251394783006077652496450, 9854615127100313024544239975139, 134283364935428822131144679491097123786

Offset: 0

Author

Jason Kimberley, Jan 26 2012

Keywords

• nonn
• more
• hard

Links

• Jason Kimberley, Index of sequences counting disconnected k-regular simple graphs with girth at least g

Crossrefs

9-regular simple graphs: A014381 (connected), this sequence (disconnected).

Disconnected regular simple graphs: A068932 (any degree), A068933 (triangular array), specified degree k: A157928 (k=0), A157928 (k=1), A165652 (k=2), A165653 (k=3), A033483 (k=4), A165655 (k=5), A165656 (k=6), A165877 (k=7), A165878 (k=8), this sequence (k=9), A185203 (k=10), A185213 (k=11).

Extensions

a(14)-a(17) from Andrew Howroyd, May 20 2020