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A073807 Number of divisors of sum of cube of divisors. 0

%I

%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.

%F a(n)=A000005[A001158(n)]=d[sigma[3, n]]

%e n=10:D={1,2,5,10}, sigma[3,10]=1+8+125+1000=1134, D[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.

%t Table[DivisorSigma[0,DivisorSigma[3,n]],{n,80}] (* _Harvey P. Dale_, Dec 13 2011 *)

%Y Cf. A000005, A001158, A062068, A073802-A073813.

%K nonn

%O 1,2

%A _Labos Elemer_, Aug 13 2002

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Last modified June 1 19:32 EDT 2020. Contains 334762 sequences. (Running on oeis4.)