A055309 Number of labeled rooted trees with n nodes and 8 leaves.

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

Offset: 9

Author

Christian G. Bower, May 11 2000

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 9..200
• Index entries for sequences related to rooted trees

Crossrefs

Column 8 of A055302.

Programs

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

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 *)

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