A055309 - OEIS

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A055309

Number of labeled rooted trees with n nodes and 8 leaves.

9, 22950, 9236700, 1731510000, 213034536000, 20154167953920, 1599866940672000, 112412172128256000, 7240640845838400000, 437993205197708160000, 25315591135036262860800

(list; graph; refs; listen; history; text; internal format)

OFFSET

9,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 9..200

Index entries for sequences related to rooted trees

FORMULA

a(n) = n! * (n-8)^2*(n-7)^2*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(9*n^4 - 234*n^3 + 2211*n^2 - 8938*n + 12960)/234101145600. - Vaclav Kotesovec, Jul 25 2014

MATHEMATICA

Table[n! * (n-8)^2*(n-7)^2*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(9*n^4 - 234*n^3 + 2211*n^2 - 8938*n + 12960)/234101145600, {n, 9, 20}] (* Vaclav Kotesovec, Jul 25 2014 *)

PROG

(Magma) [Factorial(n)*(n-8)^2*(n-7)^2*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(9*n^4 - 234*n^3 + 2211*n^2 - 8938*n + 12960)/234101145600 : n in [9..25]]; // Vincenzo Librandi, Jul 25 2014

CROSSREFS

Column 8 of A055302.

Sequence in context: A140596 A280900 A333554 * A288940 A053931 A053921

Adjacent sequences: A055306 A055307 A055308 * A055310 A055311 A055312

KEYWORD

nonn

AUTHOR

Christian G. Bower, May 11 2000

STATUS

approved