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%I #6 Jan 20 2019 13:11:49
%S 2,4,6,10,16,28,30,46,60,66,70,96,100,126,130,138,148,180,196,240,268,
%T 306,330,358,378,396,408,418,420,448,456,478,486,490,598,606,616,618,
%U 640,646,676,708,750,786,838,856,906,946,966,976,996,1050,1060,1090
%N Numbers n among A006093 such that n^2 + n - 1 is prime.
%H Harvey P. Dale, <a href="/A136241/b136241.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A091567(n) - 1.
%t Select[Prime[Range[200]]-1,PrimeQ[#^2+#-1]&] (* _Harvey P. Dale_, Jan 20 2019 *)
%Y Cf. A136240, A091568.
%K nonn
%O 1,1
%A _Lekraj Beedassy_, Dec 23 2007