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%I #17 Sep 03 2019 14:41:00
%S 2,0,3,2,7,11,5,29,47,21,44,199,32,521,284,44,2207,3571,112,9349,2168,
%T 242,353,600,1152,263,90484,5800,14510,19548,2567,3010349,5568,10102,
%U 63513,1022,103713,54018521,29134604,1461,4689,370248451,1796,151190,2118,785
%N Sum of distinct prime divisors of Lucas(n).
%H Amiram Eldar, <a href="/A219187/b219187.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = A008472(A000032(n)). - _Amiram Eldar_, Sep 03 2019
%e a(6) = 5 because Lucas(6) = 21 and the sum of the prime divisors {3, 7} equals 10.
%p with (numtheory):with(combinat,fibonacci):
%p sopf:= proc(n) local e, j; e := ifactors(fibonacci(n+1)+fibonacci(n-1))[2]:
%p add (e[j][1], j=1..nops(e)) end:
%p seq (sopf(n), n=0..100);
%t Array[If[#==1, 0, Plus@@First/@FactorInteger[LucasL[ # ]]]&, 50, 0]
%Y Cf. A000032, A008472, A080648, A219177.
%K nonn
%O 0,1
%A _Michel Lagneau_, Nov 14 2012
%E a(0) prepended by _Amiram Eldar_, Sep 03 2019