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A005464
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Number of simplices in barycentric subdivision of n-simplex.
(Formerly M5391)
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5
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1, 127, 6050, 204630, 5921520, 158838240, 4115105280, 105398092800, 2706620716800, 70309810771200, 1858166876966400, 50148628078348800, 1385482985542656000, 39245951652171264000, 1140942623868343296000, 34060437199245929472000, 1044402668566817624064000, 32895725269182358302720000
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OFFSET
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5,2
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REFERENCES
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R. Austin, R. K. Guy, and R. Nowakowski, unpublished notes, circa 1987.
R. K. Guy, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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Essentially Stirling numbers of second kind - see A028246.
a(n) = (n-5)! * Stirling2(n+2, n-4). - G. C. Greubel, Nov 22 2022
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MAPLE
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seq((d+2)!*(63*d^5-945*d^4+5355*d^3-13951*d^2+15806*d-5304)/2903040, d=5..30) ; # R. J. Mathar, Mar 19 2018
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MATHEMATICA
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Table[(n-5)!*StirlingS2[n+2, n-4], {n, 5, 35}] (* G. C. Greubel, Nov 22 2022 *)
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PROG
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(Magma) [Factorial(n-5)*StirlingSecond(n+2, n-4): n in [5..35]]; // G. C. Greubel, Nov 22 2022
(SageMath) [factorial(n-5)*stirling_number2(n+2, n-4) for n in range(5, 36)] # G. C. Greubel, Nov 22 2022
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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