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A082100 a(n) = A001157(A002110(n)), sum of squares of divisors of primorial numbers. 1

%I #13 Mar 11 2023 14:16:06

%S 5,50,1300,65000,7930000,1348100000,390949000000,141523538000000,

%T 75007475140000000,63156294067880000000,60756354893300560000000,

%U 83236206203821767200000000,140003298834828212430400000000

%N a(n) = A001157(A002110(n)), sum of squares of divisors of primorial numbers.

%H Amiram Eldar, <a href="/A082100/b082100.txt">Table of n, a(n) for n = 1..195</a>

%t s={}; p=1; prod=1; Do[prod *= (p = NextPrime@p); AppendTo[s, DivisorSigma[2, prod]], {13}]; s (* _Amiram Eldar_, Jul 31 2019 *)

%t Table[DivisorSigma[2,p],{p,FoldList[Times,Prime[Range[20]]]}] (* _Harvey P. Dale_, Mar 11 2023 *)

%Y Cf. A001157, A002110.

%K nonn

%O 1,1

%A _Labos Elemer_, Apr 14 2003

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Last modified April 19 17:51 EDT 2024. Contains 371797 sequences. (Running on oeis4.)