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Number of connected simple graphs with n vertices, n+5 edges, and vertex degrees no more than 4.
7

%I #17 Jun 05 2023 08:34:08

%S 0,0,0,0,1,3,31,298,2616,20346,140605,880737,5082279,27402524,

%T 139587885,677772953,3158930531,14212444473,62009204208,263350765116,

%U 1092085621098,4433596269478

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

%H J. B. Hendrickson and C. A. Parks, <a href="https://doi.org/10.1021/ci00001a018">Generation and Enumeration of Carbon skeletons</a>, J. Chem. Inf. Comput. Sci., 31 (1991), 101-107. See Table 2, column 6 on page 103.

%H Michael A. Kappler, <a href="http://www.daylight.com/meetings/emug04/Kappler/GenSmi.html">GENSMI: Exhaustive Enumeration of Simple Graphs</a>. [gives different a(15)]

%o (nauty/bash)

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

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

%K nonn,more

%O 1,6

%A _Jonathan Vos Post_, Dec 21 2005

%E Corrected offset and new name from _Andrey Zabolotskiy_, Nov 24 2017

%E a(15) corrected and a(16)-a(22) added by _Georg Grasegger_, Jun 05 2023