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%I #6 Jun 12 2015 11:56:02
%S 1,1,1,2,2,4,4,8,24,48,48,144,144,288,864,3456,3456,10368,10368,41472,
%T 124416,248832,248832,995328,4976640,9953280,29859840,119439360,
%U 119439360,597196800,597196800,2388787200,7166361600,14332723200,71663616000
%N a(1) = 1, a(n) = a(n-1) times largest divisor of n <= n^(1/2).
%t nxt[{n_,a_}]:=Module[{divs=Reverse[Divisors[n+1]]},{n+1,a*SelectFirst[ divs,#<=Sqrt[n+1]&]}]; Transpose[NestList[nxt,{1,1},40]][[2]] (* The program uses the SelectFirst function from Mathematica version 10 *) (* _Harvey P. Dale_, Jun 12 2015 *)
%o (PARI) A033676(n) = {local(d);if(n<2,1,d=divisors(n);d[(length(d)+1)\2])} A072488(n) = if(n<2,1,A033676(n)*A072488(n-1)) a=1;print(a);for(n=2,100,a=a*A033676(n);print(a))
%Y Cf. A072489.
%K nonn
%O 1,4
%A _Amarnath Murthy_, Jul 13 2002
%E PARI program from _Michael B. Porter_, Jan 30 2010
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