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A048619
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a(n) = LCM(binomial(n,0), ..., binomial(n,n)) / binomial(n,floor(n/2)).
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4
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1, 1, 1, 1, 2, 1, 3, 3, 4, 2, 10, 5, 30, 15, 7, 7, 56, 28, 252, 126, 60, 30, 330, 165, 396, 198, 286, 143, 2002, 1001, 15015, 15015, 7280, 3640, 1768, 884, 15912, 7956, 3876, 1938, 38760, 19380, 406980, 203490, 99484, 49742, 1144066, 572033, 1961256, 980628
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OFFSET
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0,5
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LINKS
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FORMULA
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a(n) = lcm(1..n+1)/(floor((n+3)/2)*binomial(n+1,floor((n+3)/2)). - Paul Barry, Jul 03 2006
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EXAMPLE
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If n=10 then A002944(10)=2520, A001405(10)=252, the quotient a(10)=10.
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MATHEMATICA
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Table[Apply[LCM, Binomial[n, Range[0, n]]]/Binomial[n, Floor[n/2]], {n, 0, 48}] (* Michael De Vlieger, Jun 29 2017 *)
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PROG
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(PARI) {A048619(n) = lcm(vector(n+1, i, i)) / binomial(n+1, (n+1)\2) / ((n+2)\2); }
(Magma) [Lcm([1..n+1]) div (Floor((n+3)/2)*Binomial(n+1, Floor((n+3)/2))): n in [0..50]]; // Vincenzo Librandi, Jul 10 2019
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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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EXTENSIONS
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Definition corrected and a(0)=1 prepended by Max Alekseyev, Oct 23 2015
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STATUS
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approved
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