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A055318
Number of labeled trees with n nodes and 6 leaves.
1
7, 1736, 151704, 8573040, 385363440, 15186346560, 553400527680, 19255141825920, 652932709228800, 21874544352460800, 730877395478630400, 24516805259429683200, 829582077548941516800, 28413517892377153536000
OFFSET
7,1
FORMULA
(n!/6!)*Stirling2(n-2, n-6). - Vladeta Jovovic, Jan 28 2004
a(n) = n! * (n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(15*n^3 - 240*n^2 + 1265*n - 2192)/4147200. - Vaclav Kotesovec, Jul 25 2014
MATHEMATICA
Table[n! * (n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(15*n^3 - 240*n^2 + 1265*n - 2192)/4147200, {n, 7, 20}] (* Vaclav Kotesovec, Jul 25 2014 *)
PROG
(Magma) [Factorial(n)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(15*n^3 - 240*n^2 + 1265*n - 2192)/4147200: n in [7..25]]; // Vincenzo Librandi, Jul 25 2014
CROSSREFS
Column 6 of A055314.
Sequence in context: A203012 A203697 A001424 * A117661 A206459 A172937
KEYWORD
nonn
AUTHOR
Christian G. Bower, May 11 2000
STATUS
approved