login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A342988 Number of tree-rooted planar maps with n edges and no isthmuses. 3
1, 1, 4, 23, 162, 1292, 11214, 103497, 1000810, 10039100, 103725188, 1098151276, 11866435816, 130477138014, 1456320910090, 16468167354971, 188369396046810, 2176619115192140, 25379588118629856, 298341351434460488, 3532848638781046852, 42113699799069958732 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
G.f.: A(x) satisfies A(x) = G(x*A(x)^2) where G(x) + x is the g.f. of A004304.
PROG
(PARI) \\ here J(n) gives A004304 as g.f.
J(n)={my(g=(1-sqrt(1-4*x+O(x^3*x^n)))/(2*x), h=serconvol(g, (g-1)/x)); sqrt(x/serreverse(x*h^2))}
seq(n)={my(g=J(n)-x, p=O(1)); while(serprec(p, x)<=n, p = subst(g, x, x*p^2)); Vec(p)}
CROSSREFS
Row sums of A342987.
Sequence in context: A182969 A263186 A245110 * A304074 A307402 A354497
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Apr 03 2021
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 06:57 EDT 2024. Contains 371265 sequences. (Running on oeis4.)