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A060080
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Scaled sums of squares.
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2
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1, 5, 56, 1080, 31680, 1310400, 72576000, 5181926400, 463325184000, 50697529344000, 6663103856640000, 1035678099456000000, 187913434365296640000, 39357424864287129600000, 9424067526124476825600000, 2558178330075402338304000000, 781407199004850168791040000000
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = (Sum_{k=1..n} k^2)*((n-1)!)^2 = (n+1)!*(n-1)!*(2*n+1)/3!.
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MATHEMATICA
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Table[(n + 1)! (n - 1)! (2 n + 1) / 3!, {n, 1, 30}] (* Vincenzo Librandi Jul 04 2018 *)
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PROG
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(PARI) a(n) = { (n + 1)!*(n - 1)!*(2*n + 1)/6 } \\ Harry J. Smith, Jul 01 2009
(Magma) [Factorial(n+1) * Factorial(n-1) * (2*n+1)/6: n in [1..20]]; // Vincenzo Librandi, Jul 05 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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