A344135 a(n) = Sum_{i|n, j|n, k|n} i*j*k/lcm(i,j,k).
1, 14, 22, 93, 44, 308, 74, 472, 259, 616, 158, 2046, 212, 1036, 968, 2123, 344, 3626, 422, 4092, 1628, 2212, 602, 10384, 1227, 2968, 2548, 6882, 932, 13552, 1058, 9006, 3476, 4816, 3256, 24087, 1484, 5908, 4664, 20768, 1808, 22792, 1982, 14694, 11396, 8428, 2354, 46706, 3843, 17178, 7568
Offset: 1
Programs
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Mathematica
a[n_]:= Sum[i*j*k/LCM[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/lcm([i, j, k]))));
Formula
If p is prime, a(p) = 4 + 3*p + p^2.