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%I #15 Jun 13 2017 14:28:02
%S 4,9,16,25,36,49,121,196,289,324,361,529,625,729,1024,1296,1681,1849,
%T 2916,3600,4225,4761,5184,5929,6400,6724,6889,7569,7744,8464,8649,
%U 9604,12100,13689,14641,14884,15876,16129,18225,18496,19044,22201,22500,24025,24649,25281,28224
%N Square numbers n such that n^2 - n - 1 is prime.
%C Or, squares in A002328: a(1) = 4 = A002328(2), a(2) = 9 = A002328(6), a(1) = 16 = A002328(11).
%C The corresponding primes, 11, 71, 239, 599, 1259, 2351, 14519, 38219, 83231, 104651, 129959, 279311, 389999, 530711, 1047551, 1678319, are a subsequence of A002327.
%t Select[Table[n^2, {n, 100}], PrimeQ[#^2 - # - 1] &]
%o (PARI) list(lim)=my(v=List()); for(n=2,sqrtint(lim\1), if(isprime(n^2-n-1), listput(v,n))); Vec(v) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Intersection of A002328 and A000290. Cf. A002327.
%K nonn
%O 1,1
%A _Zak Seidov_, Apr 13 2014
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