A055316 - OEIS

%I #17 Sep 08 2022 08:45:01

%S 5,210,5250,109200,2116800,40219200,768398400,14968800000,

%T 299675376000,6193291104000,132456516192000,2935293064704000,

%U 67432408243200000,1605928737853440000,39636028549877760000

%N Number of labeled trees with n nodes and 4 leaves.

%H Vincenzo Librandi, <a href="/A055316/b055316.txt">Table of n, a(n) for n = 5..200</a>

%H <a href="/index/Tra#trees">Index entries for sequences related to trees</a>

%F (n!/4!)*stirling2(n-2, n-4). - _Vladeta Jovovic_, Jan 28 2004

%F a(n) = n! * (n-4)*(n-3)*(n-2)*(3*n-11)/576. - _Vaclav Kotesovec_, Jul 25 2014

%t Table[n! * (n-4)*(n-3)*(n-2)*(3*n-11)/576,{n,5,20}] (* _Vaclav Kotesovec_, Jul 25 2014 *)

%o (Magma) [Factorial(n)*(n-4)*(n-3)*(n-2)*(3*n-11)/576: n in [5..25]]; // _Vincenzo Librandi_, Jul 25 2014

%Y Column 4 of A055314.

%K nonn

%O 5,1

%A _Christian G. Bower_, May 11 2000