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%I #15 May 12 2021 10:15:45
%S 1,23,46,219,116,1058,218,1507,883,2668,518,10074,716,5014,5336,8819,
%T 1208,20309,1502,25404,10028,11914,2186,69322,5691,16468,12628,47742,
%U 3452,122728,3938,46995,23828,27784,25288,193377,5588,34546,32936,174812,6848,230644,7526,113442,102428,50278,8978
%N a(n) = Sum_{i|n, j|n, k|n} i*j*k/gcd(i,j,k).
%F If p is prime, a(p) = 1 + 3*p + 4*p^2.
%t a[n_]:= Sum[i*j*k/GCD[i,j,k], {i, (d = Divisors[n])}, {j, d}, {k, d}]; Array[a, 50] (* _Amiram Eldar_, May 10 2021 *)
%o (PARI) a(n) = sumdiv(n, i, sumdiv(n, j, sumdiv(n, k, i*j*k/gcd([i, j, k]))));
%Y Cf. A064950, A344132, A344134, A344135.
%K nonn,mult
%O 1,2
%A _Seiichi Manyama_, May 10 2021
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