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A234861 Sum of the distinct prime divisors of n^3 - 1. 1

%I

%S 0,7,15,10,33,48,24,80,22,40,33,168,66,224,250,28,309,24,132,440,470,

%T 23,99,624,43,61,772,274,89,55,341,189,1125,411,129,86,79,1520,251,

%U 563,1730,193,643,333,141,118,123,241,67,2558,393,939,431,3024,97,150

%N Sum of the distinct prime divisors of n^3 - 1.

%H Vincenzo Librandi, <a href="/A234861/b234861.txt">Table of n, a(n) for n = 1..1000</a>

%e a(3) = 15 because 3^3-1 = 26 and the sum of the 2 distinct prime divisors {2, 13} is 15.

%t Table[Total[Transpose[FactorInteger[n^3 - 1]][[1]]], {n, 50}]

%Y Cf. A062835.

%K nonn

%O 1,2

%A _Vincenzo Librandi_, Jan 01 2014

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Last modified October 5 23:01 EDT 2022. Contains 357261 sequences. (Running on oeis4.)