A055308 Number of labeled rooted trees with n nodes and 7 leaves.

8, 9144, 2178000, 270111600, 23449219200, 1635398519040, 98861289246720, 5425893817344000, 278673669001728000, 13673851998782976000, 650477329618365849600, 30322668859342072012800

Offset: 8

Author

Christian G. Bower, May 11 2000

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 8..200
• Index entries for sequences related to rooted trees

Crossrefs

Column 7 of A055302.

Programs

Magma

[Factorial(n)*(n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(63*n^5- 1890*n^4+22365*n^3-130186*n^2+371672*n-414720)/14631321600: n in [8..25]]; // Vincenzo Librandi, Jul 25 2014

Mathematica

Table[n! * (n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(63*n^5 - 1890*n^4 + 22365*n^3 - 130186*n^2 + 371672*n - 414720)/14631321600,{n,8,20}] (* Vaclav Kotesovec, Jul 25 2014 *)

Formula

a(n) = n! * (n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(n-1)*(63*n^5 - 1890*n^4 + 22365*n^3 - 130186*n^2 + 371672*n - 414720)/14631321600. - Vaclav Kotesovec, Jul 25 2014