A055305 Number of labeled rooted trees with n nodes and 4 leaves.

5, 450, 18900, 588000, 15876000, 400075200, 9779616000, 237105792000, 5779453680000, 142845262560000, 3599700616512000, 92818726640640000, 2454539660052480000, 66664716210892800000, 1861170036255129600000

Offset

5,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 5..200

Index entries for sequences related to rooted trees

Formula

a(n) = n! * (n-4)^2*(n-3)^2*(n-2)*(n-1)/1152. - Vaclav Kotesovec, Jul 25 2014

Mathematica

Table[n! * (n-4)^2*(n-3)^2*(n-2)*(n-1)/1152, {n, 5, 20}] (* Vaclav Kotesovec, Jul 25 2014 *)

Prog

(Magma) [Factorial(n)*(n-4)^2*(n-3)^2*(n-2)*(n-1)/1152 : n in [5..25]]; // Vincenzo Librandi, Jul 25 2014

Crossrefs

Column 4 of A055302.

Sequence in context: A212042 A177026 A300544 * A300971 A300928 A221626

Adjacent sequences: A055302 A055303 A055304 * A055306 A055307 A055308

Keyword

nonn

Author

Christian G. Bower, May 11 2000

Status

approved