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%I #11 Mar 07 2021 17:47:03
%S 1,2,3,10,30,100,371,1419,5764,24482,107583,487647,2271488,10847623
%N Number of unlabeled connected nonplanar graphs with n edges with degree >= 3 at each node.
%C First differs from A338583 for n = 13. All unlabeled nonplanar graphs with n <= 12 edges and degree >= 3 at each node are 3-connected. For this reason the illustrations of the graphs are identical up to n = 12. The first differences for n = 13 and n = 14 are shown in the illustrations of A338584.
%H Hugo Pfoertner, <a href="/A338583/a338583.pdf">Illustrations of terms a(9) - a(12)</a>, from A338583.
%H Hugo Pfoertner, <a href="/A338584/a338584.pdf">Illustration of terms a(13) and a(14)</a>, showing graphs counted in this sequence, but not in A338583 (illustrations from A338584).
%H Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/a338593_d3np.zip">Unlabeled nonplanar graphs with vertex degree >=3 for n<=19 edges</a>, list in PARI-readable format.
%F a(n) = A338604(n) - A338594(n).
%o (PARI) \\ It is assumed that the a338593.gp file (from the linked zip archive) has been read before, i.e., \r [path]a338593.gp
%o for(k=9,#EdgeDataNonplanarDegge3,print1(#EdgeDataNonplanarDegge3[k],", "));
%o \\ printing of the edge lists of the graphs for n <= 11
%o print(EdgeDataNonplanarDegge3[9..11])
%Y Cf. A007112, A002840, A123545, A338511, A338583, A338584, A338594, A338604.
%K nonn,more
%O 9,2
%A _Hugo Pfoertner_, Nov 21 2020
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