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%I #20 May 15 2017 11:32:03
%S 11,19,31,59,71,79,131,139,151,179,191,199,211,239,251,271,311,331,
%T 359,379,419,431,439,479,491,499,571,599,619,631,659,691,719,739,751,
%U 811,839,859,911,919,971,991,1019,1031,1039,1051,1091,1151,1171,1231,1259
%N Primes p that divide Lucas((p-1)/2), where Lucas is A000032.
%C Lucas numbers A000032(n) = Fibonacci(n-1) + Fibonacci(n+1) = A000045(n-1) + A000045(n+1).
%C Subsequence of A002145, A040105, A064739, A003626, A076518, and A040147.
%C Final digit of a(n) is 1 or 9.
%C A002145 is the union of this sequence and A122870, Primes p that divide Lucas((p+1)/2).
%C Conjecture: This sequence is just the primes congruent to 11 or 19 mod 20. - _Charles R Greathouse IV_, May 25 2011
%H Vincenzo Librandi, <a href="/A122869/b122869.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LucasNumber.html">Lucas Number</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GaussianPrime.html">Gaussian Prime</a>.
%t Select[Prime[Range[1000]],IntegerQ[(Fibonacci[(#1-1)/2-1]+Fibonacci[(#1-1)/2+1])/#1]&]
%Y Cf. A000032, A000045, A122870, A002145, A040105, A053032, A064739, A003626, A076518.
%K nonn
%O 1,1
%A _Alexander Adamchuk_, Sep 16 2006
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