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%I #16 Jul 13 2023 01:17:47
%S 1,3,6,2,12,18,8,12,2,20,18,12,8,24,36,4,32,6,24,24,24,30,36,72,4,24,
%T 32,16,24,60,36,16,60,48,60,4,16,72,24,80,24,72,24,36,24,60,60,24,8,
%U 12,96,16,20,96,80,96,50,40,72,72,16,108,16,8,54,100,12,64,108,100,32,24
%N Number of divisors of sum of cube of divisors.
%C a(n) = 2 for n in A063783. - _Robert Israel_, Jul 12 2023
%H Robert Israel, <a href="/A073807/b073807.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000005(A001158(n)).
%e For n=10: D={1,2,5,10}, 1+8+125+1000=1134, divisors(1134)={1,2,3,6,7,9,14,18,21,27,42,54,63,81,126,162,189,378,567,1134} so a(10)=20.
%p f:= n -> numtheory:-tau(numtheory:-sigma[3](n)):
%p map(f, [$1..100]); # _Robert Israel_, Jul 12 2023
%t Table[DivisorSigma[0,DivisorSigma[3,n]],{n,80}] (* _Harvey P. Dale_, Dec 13 2011 *)
%o (PARI) a(n) = numdiv(sigma(n, 3)); \\ _Michel Marcus_, Jul 13 2023
%Y Cf. A000005, A001158, A062068, A063783, A073802-A073813.
%K nonn
%O 1,2
%A _Labos Elemer_, Aug 13 2002
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