%I #7 Mar 23 2023 07:36:52
%S 0,2,3,4,5,30,7,16,9,70,11,84,13,126,120,64,17,198,19,180,210,286,23,
%T 336,25,390,81,308,29,930,31,256,462,646,420,468,37,798,624,720,41,
%U 1722,43,660,630,1150,47,1344,49,1350,1020,884,53,1782,880,1232,1254,1798,59
%N a(n) = n * Sum_{p|n, p prime} lcm(p,n/p) / p.
%C If p is prime, a(p) = p * Sum_{p|p} lcm(p,p/p) / p = p * p/p = p.
%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>
%e a(18) = 18 * Sum_{p|18} lcm(p,18/p) / p = 18 * (lcm(2,9)/2 + lcm(3,6)/3) = 18 * (9 + 2) = 198.
%t Table[n*Sum[(1/k) LCM[k, n/k] (PrimePi[k] - PrimePi[k - 1]) (1 - Ceiling[n/k] + Floor[n/k]), {k, n}], {n, 100}]
%Y Cf. A345302.
%K nonn
%O 1,2
%A _Wesley Ivan Hurt_, Jun 13 2021
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