A234646 - OEIS

%I #5 Jan 05 2014 05:59:20

%S 0,2,3,9,18,12,38,45,22,80,31,42,39,166,69,213,258,25,326,14,137,434,

%T 486,18,91,616,41,65,786,281,111,28,345,177,1135,402,147,95,90,1490,

%U 271,559,1766,165,639,315,175,115,105,201,82,2566,439,924,432,2980,114

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

%H Vincenzo Librandi, <a href="/A234646/b234646.txt">Table of n, a(n) for n = 0..1000</a>

%e a(3) = 9 because 3^3+1 = 28 and the sum of the 2 distinct prime divisors {2, 7} is 9.

%t Join[{0}, Table[Total[Transpose[FactorInteger[n^3 + 1]][[1]]], {n, 60}]]

%Y Cf. A193462.

%K nonn

%O 0,2

%A _Vincenzo Librandi_, Jan 01 2014