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A338593 Number of unlabeled connected nonplanar graphs with n edges with degree >= 3 at each node. 7
1, 2, 3, 10, 30, 100, 371, 1419, 5764, 24482, 107583, 487647, 2271488, 10847623 (list; graph; refs; listen; history; text; internal format)
OFFSET
9,2
COMMENTS
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.
LINKS
Hugo Pfoertner, Illustration of terms a(13) and a(14), showing graphs counted in this sequence, but not in A338583 (illustrations from A338584).
Hugo Pfoertner, Unlabeled nonplanar graphs with vertex degree >=3 for n<=19 edges, list in PARI-readable format.
FORMULA
a(n) = A338604(n) - A338594(n).
PROG
(PARI) \\ It is assumed that the a338593.gp file (from the linked zip archive) has been read before, i.e., \r [path]a338593.gp
for(k=9, #EdgeDataNonplanarDegge3, print1(#EdgeDataNonplanarDegge3[k], ", "));
\\ printing of the edge lists of the graphs for n <= 11
print(EdgeDataNonplanarDegge3[9..11])
CROSSREFS
Sequence in context: A319189 A301971 A319671 * A270363 A131764 A066706
KEYWORD
nonn,more
AUTHOR
Hugo Pfoertner, Nov 21 2020
STATUS
approved

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Last modified March 29 10:22 EDT 2024. Contains 371268 sequences. (Running on oeis4.)