A344133 a(n) = Sum_{i|n, j|n, k|n} i*j*k/gcd(i,j,k).
1, 23, 46, 219, 116, 1058, 218, 1507, 883, 2668, 518, 10074, 716, 5014, 5336, 8819, 1208, 20309, 1502, 25404, 10028, 11914, 2186, 69322, 5691, 16468, 12628, 47742, 3452, 122728, 3938, 46995, 23828, 27784, 25288, 193377, 5588, 34546, 32936, 174812, 6848, 230644, 7526, 113442, 102428, 50278, 8978
Offset: 1
Programs
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Mathematica
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 *) -
PARI
a(n) = sumdiv(n, i, sumdiv(n, j, sumdiv(n, k, i*j*k/gcd([i, j, k]))));
Formula
If p is prime, a(p) = 1 + 3*p + 4*p^2.