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A055324
Number of labeled trees with n nodes and 12 leaves.
2
13, 372554, 714236250, 453911421600, 156507084115200, 36555247168352640, 6528715119143118720, 960135043767367104000, 122086105154945279712000, 13885903109630633425344000, 1447862009053077400092710400, 140958354488116955062668595200
OFFSET
13,1
FORMULA
a(n) = (n!/12!)*Stirling2(n-2, n-12). - Vladeta Jovovic, Jan 28 2004
a(n) = n! * (n-12)*(n-11)*(n-10)*(n-9)*(n-8)*(n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(99*n^9 - 9207*n^8 + 377586*n^7 - 8955870*n^6 + 135276603*n^5 - 1348112183*n^4 + 8853485696*n^3 - 36897359092*n^2 + 88399944688*n - 92577669120) / 176211865192366080000. - Vaclav Kotesovec, Jul 25 2014
MATHEMATICA
Table[n! * (n-12)*(n-11)*(n-10)*(n-9)*(n-8)*(n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(99*n^9 - 9207*n^8 + 377586*n^7 - 8955870*n^6 + 135276603*n^5 - 1348112183*n^4 + 8853485696*n^3 - 36897359092*n^2 + 88399944688*n - 92577669120) / 176211865192366080000, {n, 13, 25}] (* Vaclav Kotesovec, Jul 25 2014 *)
Table[(n!/12!)*StirlingS2[n-2, n-12], {n, 13, 30}] (* G. C. Greubel, Feb 07 2018 *)
PROG
(Magma) [Factorial(n)*(n-12)*(n-11)*(n-10)*(n-9)*(n-8)*(n-7)*(n-6)*(n-5)*(n-4)*(n-3)*(n-2)*(99*n^9 - 9207*n^8 + 377586*n^7 - 8955870*n^6 + 135276603*n^5 - 1348112183*n^4 + 8853485696*n^3 - 36897359092*n^2 + 88399944688*n - 92577669120) / 176211865192366080000: n in [13..25]]; // Vincenzo Librandi, Jul 25 2014
(PARI) for(n=13, 30, print1((n!/12!)*stirling(n-2, n-12, 2), ", ")) \\ G. C. Greubel, Feb 07 2018
(Magma) [(Factorial(n)/Factorial(12))*StirlingSecond(n-2, n-12): n in [13..30]]; // G. C. Greubel, Feb 07 2018
CROSSREFS
Column 12 of A055314.
Sequence in context: A228522 A274229 A013798 * A228538 A055313 A128669
KEYWORD
nonn
AUTHOR
Christian G. Bower, May 11 2000
EXTENSIONS
Missing a(24) inserted by Andrew Howroyd, Feb 23 2018
STATUS
approved