OFFSET
0,5
REFERENCES
J. A. Wright, There are 718 6-point topologies, quasi-orderings and transgraphs, Notices Amer. Math. Soc., 17 (1970), p. 646, Abstract #70T-A106.
LINKS
S. R. Finch, Series-parallel networks
S. R. Finch, Series-parallel networks, July 7, 2003. [Cached copy, with permission of the author]
FORMULA
From Geoffrey Critzer, Jul 09 2022: (Start)
E.g.f.: 1 + log(A(x)) - A(x)(1-1/A(x))^2 where A(x) is the e.g.f. for A001035.
MATHEMATICA
nn = 18; A[x_] := Total[Cases[Import["https://oeis.org/A001035/b001035.txt",
"Table"], {_, _}][[All, 2]]*Table[x^(i - 1)/(i - 1)!, {i, 1, 19}]];
Range[0, nn]! CoefficientList[ Series[(1 + Log[A[x]]) - A[ x] (1 - 1/A[x])^2 , {x, 0, nn}], x] (* Geoffrey Critzer, Jul 09 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
John A. Wright.
EXTENSIONS
a(8)-a(18) from Geoffrey Critzer, Jul 09 2022
a(0) changed to 1 by Geoffrey Critzer, Jul 10 2022
STATUS
approved