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%I #8 May 08 2022 12:16:46
%S 4,6,4,9,10,6,14,15,4,9,10,21,22,6,25,26,9,14,15,4,33,34,35,9,38,39,
%T 10,21,22,15,46,6,49,25,51,26,9,55,14,57,58,15,62,21,4,65,33,34,69,35,
%U 9,74,25,38,77,39,10,9,82,21,85,86,87,22,15,91,46,93,94,95,6,49,33,25
%N Greatest semiprime divisor of n-th composite number.
%H Zak Seidov, <a href="/A088740/b088740.txt">Table of n, a(n) for n = 1..1000</a>
%t Reap[Do[If[! PrimeQ[n], fl = Flatten[Table[#[[1]], {#[[2]]}] & /@ FactorInteger[n]]; Sow[fl[[-1]]*fl[[-2]]]], {n, 4, 1200}]][[2, 1]]; (* _Zak Seidov_, Mar 18 2013 *)
%t gsd[n_]:=Max[Select[Divisors[n],PrimeOmega[#]==2&]]; gsd/@Select[Range[ 200],CompositeQ] (* _Harvey P. Dale_, May 08 2022 *)
%Y Cf. A088739, A002808, A001358.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Oct 12 2003
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