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%I #16 Dec 09 2024 05:28:27
%S 8,42,104,224,264,780,592,1680,1520,2880,1896,5642,2968,5808,8736,
%T 9548,7200,15360,8440,19488,19032,23040,14448,49920,23560,31836,32912,
%U 53312,34200,77688,38912,70812,62088,74088,67584,152320,56392,107520,99736
%N Sum of the divisors of n^3 - 1.
%H Vincenzo Librandi, <a href="/A234860/b234860.txt">Table of n, a(n) for n = 2..1001</a>
%F From _Amiram Eldar_, Dec 09 2024: (Start)
%F a(n) = A000203(A068601(n)).
%F Sum_{k=2..n} a(k) = c * n^4 + O((n*log(n))^3), where c = (83/288) * Product_{primes p == 1 (mod 3)} ((p^2+2)/(p^2-1)) * Product_{primes p == 2 (mod 3)} (p^2/(p^2-1)) = 0.4499262799... . (End)
%t Table[Total[Divisors[n^3 - 1]], {n, 2, 50}]
%o (Magma) [SumOfDivisors(n^3-1): n in [2..50]];
%o (PARI) a(n) = sigma(n^3-1); \\ _Amiram Eldar_, Dec 09 2024
%Y Cf. A000203, A062835, A065764, A068601, A175926, A193433, A333240.
%K nonn,easy,changed
%O 2,1
%A _Vincenzo Librandi_, Jan 01 2014
%E Offset corrected by _Amiram Eldar_, Dec 09 2024