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Product{<n/k>: k=1,2,...,n}, where <x> denotes the integer second nearest to x. (For x=(2h+1)/2, <x> is defined to be h, not h+1; if x is an integer, then <x> is defined to be x+1.)
2

%I #3 Mar 30 2012 18:57:04

%S 2,6,8,60,48,336,576,2160,3840,25344,17280,262080,322560,829440,

%T 1548288,21150720,16588800,73543680,139345920,766402560,1459814400,

%U 9157017600,4087480320,90574848000,130427781120,361184624640

%N Product{<n/k>: k=1,2,...,n}, where <x> denotes the integer second nearest to x. (For x=(2h+1)/2, <x> is defined to be h, not h+1; if x is an integer, then <x> is defined to be x+1.)

%C <x> = 2[x]-[x+1/2]+1 (Joe Stickles, University of Evansville).

%e a(6) = <6/1>*<6/2>*<6/3>*<6/4>*<6/5>*<6/6> = 7*4*3*1*2*2 = 336.

%Y Cf. A075999, 2*A076001.

%K nonn

%O 1,1

%A _Clark Kimberling_, Sep 29 2002