login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A055329 Number of rooted identity trees with n nodes and 4 leaves. 2
2, 11, 40, 109, 254, 524, 998, 1774, 2995, 4833, 7525, 11346, 16659, 23877, 33528, 46203, 62637, 83643, 110213, 143432, 184600, 235129, 296687, 371072, 460382, 566866, 693121, 841917, 1016422, 1220001, 1456473, 1729878, 2044767, 2405940 (list; graph; refs; listen; history; text; internal format)
OFFSET

8,1

LINKS

Andrew Howroyd, Table of n, a(n) for n = 8..1000

Index entries for sequences related to rooted trees

Index entries for linear recurrences with constant coefficients, signature (3,-1,-4,3,-1,3,0,-3,1,-3,4,1,-3,1).

FORMULA

G.f.: -x^8*(x^6+5*x^4+8*x^3+9*x^2+5*x+2)/((x-1)^7*(x+1)^3*(x^2+1)*(x^2+x+1)). - Colin Barker, Nov 07 2012

PROG

(PARI) Vec((2 + 5*x + 9*x^2 + 8*x^3 + 5*x^4 + x^6)/((1 - x)^7*(1 + x)^3*(1 + x^2)*(1 + x + x^2)) + O(x^40)) \\ Andrew Howroyd, Aug 28 2018

CROSSREFS

Column 4 of A055327.

Sequence in context: A296593 A125064 A274326 * A193005 A152895 A308524

Adjacent sequences:  A055326 A055327 A055328 * A055330 A055331 A055332

KEYWORD

nonn,easy

AUTHOR

Christian G. Bower, May 12 2000

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 11 21:35 EDT 2021. Contains 343808 sequences. (Running on oeis4.)