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%I #17 Oct 18 2013 18:39:38
%S 0,2,5,7,17,15,37,7,18,43,101,63,34,24,197,115,257,36,18,183,401,32,
%T 102,60,577,315,677,80,162,423,70,52,46,116,102,615,1297,144,22,763,
%U 1601,31,358,44,162,1015,102,37,466,1203,102,1303,546,288,2917,108,3137
%N Sum of the distinct prime divisors of n^2+1.
%H Harvey P. Dale, <a href="/A193462/b193462.txt">Table of n, a(n) for n = 0..1000</a>
%e a(7) = 7 because 7^2+1 = 2*5^2 and the sum of the 2 distinct prime divisors {2, 5} is 7.
%p with(numtheory):for n from 0 to 110 do:x:=factorset(n^2+1):n1:=nops(x):s:=0:for m from 1 to n1 do: s:=s+x[m]:od: printf(`%d, `, s):od:
%t Join[{0},Table[Total[Transpose[FactorInteger[n^2+1]][[1]]],{n,60}]] (* _Harvey P. Dale_, Oct 18 2013 *)
%Y Cf. A193432, A193433.
%K nonn
%O 0,2
%A _Michel Lagneau_, Jul 28 2011