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a(n) = A003418(n)/A034386(n).
6

%I #28 Dec 26 2020 11:13:07

%S 1,1,1,2,2,2,2,4,12,12,12,12,12,12,12,24,24,24,24,24,24,24,24,24,120,

%T 120,360,360,360,360,360,720,720,720,720,720,720,720,720,720,720,720,

%U 720,720,720,720,720,720,5040,5040,5040,5040,5040,5040,5040,5040,5040

%N a(n) = A003418(n)/A034386(n).

%H Michael De Vlieger, <a href="/A045948/b045948.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>

%e n=11: lcm(1..11) = 27720 = 8*9*5*7*11 = 2310*12. A034386(11)=2310, so the quotient is 12. Thus a(11) = 12.

%t Table[Exp[Sum[MangoldtLambda[n], {n, 1, m}]]/ Product[x, {x, Prime[Range[PrimePi[m]]]}], {m, 1, 57}] (* _Fred Daniel Kline_, Apr 02 2015 *)

%o (PARI) a(n)=lcm([1..n])/prod(i=1,primepi(n),prime(i)) \\ _Charles R Greathouse IV_, Apr 02 2015; corrected by _Michel Marcus_, Dec 26 2020

%Y Cf. A003418, A034386, A002110, A000142, A049536, A048148.

%K nonn

%O 1,4

%A _Labos Elemer_