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%I #17 Nov 24 2022 04:21:17
%S 1,1,5,5,37,47,69,263,1321,1429,9901,17249,113741,161191,32867,158363,
%T 3157279,5777183,18358381,20649997,9258477,10610101,24266365,
%U 2411391361,2299685867,1072410923,22804031069,27841579901,395718022103
%N Numerators of Sum_{k=1..n} 1/lcm(n,k).
%C a(n)/A074949(n) is the asymptotic density of numbers that are divisible by their digital root in base n+1 (e.g., A064807 for base 10). - _Amiram Eldar_, Nov 24 2022
%H Amiram Eldar, <a href="/A074947/b074947.txt">Table of n, a(n) for n = 1..2308</a>
%e 1, 1, 5/6, 5/6, 37/60, 47/60, 69/140, 263/420, 1321/2520, 1429/2520, ...
%t a[n_] := Numerator @ Sum[1/LCM[k, n], {k, 1, n}]; Array[a, 30] (* _Amiram Eldar_, Jan 31 2021 *)
%o (PARI) a(n)=numerator(sum(i=1,n,1/lcm(n,i)))
%Y Cf. A064807, A074949 (denominators).
%K easy,frac,nonn
%O 1,3
%A _Benoit Cloitre_, Oct 05 2002
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