A112425 Number of connected simple graphs with n vertices, n+5 edges, and vertex degrees no more than 4.

0, 0, 0, 0, 1, 3, 31, 298, 2616, 20346, 140605, 880737, 5082279, 27402524, 139587885, 677772953, 3158930531, 14212444473, 62009204208, 263350765116, 1092085621098, 4433596269478

Offset: 1

Author

Jonathan Vos Post, Dec 21 2005

Keywords

• nonn
• more

Links

• J. B. Hendrickson and C. A. Parks, Generation and Enumeration of Carbon skeletons, J. Chem. Inf. Comput. Sci., 31 (1991), 101-107. See Table 2, column 6 on page 103.
• Michael A. Kappler, GENSMI: Exhaustive Enumeration of Simple Graphs. [gives different a(15)]

Crossrefs

The analogs for n+k edges with k = -1, 0, ..., 7 are: A000602, A036671, A112410, A112619, A112408, A112424, this sequence, A112426, A112442. Cf. A121941.

Programs

nauty

for n in {5..13}; do geng -c -D4 ${n} $((n+5)):$((n+5)) -u; done # Andrey Zabolotskiy, Nov 24 2017

Extensions

Corrected offset and new name from Andrey Zabolotskiy, Nov 24 2017

a(15) corrected and a(16)-a(22) added by Georg Grasegger, Jun 05 2023