%I #15 Feb 21 2024 10:32:59
%S 0,1,4,17,118,1198,17133,311757,6803203
%N Number of unlabeled nonseparable (or 2-connected) loopless multigraphs with circuit rank n and degree >= 3 at each node.
%H Martin Dowd, <a href="https://doi.org/10.12732/ijpam.v95i2.14">Some results on reconstructibility of colored graphs</a>, IJPAM, 95 (2014), 309-321. Gives the sequence up to a(8) in Figure 1.
%H Martin Dowd, <a href="https://www.researchgate.net/publication/378179019_fsmg_rel">The source code of an implementation of the algorithm from the paper and data files containing the output graphs</a>, 2024.
%H Zhizheng Ye, Xuewen Huang, Chuanyu Wu, Xianglei Xue and Liang Sun, <a href="https://doi.org/10.1016/j.mechmachtheory.2023.105227">Synthesis of contracted graph for planar nonfractionated simple-jointed kinematic chain based on similarity information</a>, Mechanism and Machine Theory, 181 (2023), 105227. Gives the sequence in Table 3 with an erroneous term a(8) = 311737.
%F a(n) = Sum_{k=2..2*n-2} A046752(n + k - 1, k).
%Y Diagonal sums of A046752.
%Y Cf. A002935, A360864.
%K nonn,more
%O 1,3
%A _Andrew Howroyd_, Feb 25 2023
%E a(8) from the paper by Martin Dowd (2014) and a(9) from Martin Dowd (personal communication) added by _Andrey Zabolotskiy_, Feb 21 2024