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A225558 a(n) = A003418(n)/A000793(n).

%I A225558 #16 Feb 27 2016 15:11:37
%S A225558 1,1,1,2,3,10,10,35,56,126,84,924,462,6006,4290,3432,5148,58344,58344,
%T A225558 554268,554268,554268,554268,6374082,6374082,21246940,21246940,
%U A225558 52151580,34767720,924241890,504131940,15628090140,26447537160,26447537160,15628090140
%N A225558 a(n) = A003418(n)/A000793(n).
%H A225558 Alois P. Heinz, <a href="/A225558/b225558.txt">Table of n, a(n) for n = 0..1000</a>
%F A225558 a(n) = A003418(n)/A000793(n).
%F A225558 A074115(n)/a(n) = A025527(n).
%p A225558 g:= proc(n) g(n):= `if`(n=0, 1, ilcm(n, g(n-1))) end:
%p A225558 b:= proc(n, i) option remember; local p;
%p A225558       p:= `if`(i<1, 1, ithprime(i));
%p A225558       `if`(n=0 or i<1, 1, max(b(n, i-1),
%p A225558            seq(p^j*b(n-p^j, i-1), j=1..ilog[p](n))))
%p A225558     end:
%p A225558 a:= n->g(n)/b(n, `if`(n<8, 3,
%p A225558     numtheory[pi](ceil(1.328*isqrt(n*ilog(n)))))):
%p A225558 seq(a(n), n=0..40); # _Alois P. Heinz_, May 22 2013
%t A225558 b[n_, i_] := b[n, i] = Module[{p}, p = If[i<1, 1, Prime[i]]; If[n==0 || i<1, 1, Max[b[n, i-1], Table[p^j*b[n-p^j, i-1], {j, 1, Log[p, n] // Floor }]]]]; a[0]=1; a[n_] := LCM @@ Range[n] / b[n, If[n<8, 3, PrimePi[ Ceiling[ 1.328*Sqrt[n*Log[n] // Floor]]]]]; Table[a[n], {n, 0, 40}] (* _Jean-François Alcover_, Feb 27 2016, after _Alois P. Heinz_ *)
%Y A225558 Cf. A000793, A003418.
%K A225558 nonn
%O A225558 0,4
%A A225558 _Antti Karttunen_, May 10 2013