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A055307
Number of labeled rooted trees with n nodes and 6 leaves.
1
7, 3528, 486864, 39160800, 2357586000, 119409111360, 5426122141440, 230006844587520, 9326497051872000, 367969396354560000, 14295131088292454400, 551514022702420377600, 21263333439482226892800
OFFSET
7,1
FORMULA
a(n) = n! * (n-6)^2*(n-5)^2*(n-4)*(n-3)*(n-2)*(n-1)*(3*n^2 - 29*n + 64)/8294400. - Vaclav Kotesovec, Jul 25 2014
E.g.f: x^7*(120*x^4+444*x^3+328*x^2+52*x+1)/(720*(1-x)^11). - Robert Israel, Jul 25 2014
MAPLE
seq(n! * (n-6)^2*(n-5)^2*(n-4)*(n-3)*(n-2)*(n-1)*(3*n^2 - 29*n + 64)/8294400, n=7..100); # Robert Israel, Jul 25 2014
MATHEMATICA
Table[n! * (n-6)^2*(n-5)^2*(n-4)*(n-3)*(n-2)*(n-1)*(3*n^2 - 29*n + 64)/8294400, {n, 7, 20}] (* Vaclav Kotesovec, Jul 25 2014 *)
PROG
(Magma) [Factorial(n)*(n-6)^2*(n-5)^2*(n-4)*(n-3)*(n-2)*(n-1)*(3*n^2-29*n+ 64)/8294400: n in [7..25]]; // Vincenzo Librandi, Jul 25 2014
CROSSREFS
Column 6 of A055302.
Sequence in context: A172956 A236368 A350018 * A052496 A216935 A024100
KEYWORD
nonn
AUTHOR
Christian G. Bower, May 11 2000
STATUS
approved