%I #24 May 18 2015 10:04:25
%S 2,13,17,37,53,73,97,113,137,157,173,193,197,233,257,277,293,313,317,
%T 337,353,373,397,433,457,557,577,593,613,617,653,673,677,733,757,773,
%U 797,853,857,877,937,953,977,997,1013,1033,1093,1097,1117,1153,1193,1213
%N 2 together with odd primes p that divide Fibonacci[(p+1)/2].
%C Primes of the form 2x^2+2xy+13y^2. Discriminant = -100. - _T. D. Noe_, May 02 2008
%C Primes of the form a^2 + b^2 such that a^2 == b^2 (mod 5). - _Thomas Ordowski_, May 18 2015
%H Giovanni Resta, <a href="/A122487/b122487.txt">Table of n, a(n) for n = 1..1000</a>
%F Except for 2, the primes are congruent to {13, 17} (mod 20). - _T. D. Noe_, May 02 2008
%F 2 together with all primes p == {13, 17} (mod 20). - _Thomas Ordowski_, May 18 2015
%t Select[Prime[Range[1000]],IntegerQ[Fibonacci[(#1+1)/2]/#1]&]
%o (PARI) is(n)=my(k=n%20); (k==13||k==17||k==2) && isprime(n) \\ _Charles R Greathouse IV_, May 18 2015
%Y Cf. A000045, A033205, A045468, A003631, A053028, A139827.
%K nonn,easy
%O 1,1
%A _Alexander Adamchuk_, Sep 16 2006
%E Definition changed by _T. D. Noe_, May 02 2008
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