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%I #9 Dec 24 2019 08:29:17
%S 3,5,17681,21377,21587,33599,41201,41411,70139,74759,84629,109619,
%T 114197,130619,155861,160481,174467,219407,222977,223439,230999,
%U 235787,243431,284129,285641,287279,300929,325079,373211,386987,389297,397151
%N Lesser of twin primes (p,q=p+2) such that p*q-p-q and p*q+p+q are primes.
%C Or, primes p such that p+2, p^2-2 and 2 + 4*p + p^2 are primes. Intersection of A128550 and A128551.
%C The number of such p's <= 10^n: 2, 2, 2, 2, 11, 56, 320, 1772, ..., . - _Robert G. Wilson v_, Mar 11 2007
%H Amiram Eldar, <a href="/A126334/b126334.txt">Table of n, a(n) for n = 1..10000</a>
%t fQ[n_] := Block[{p = Prime[n], q = Prime[n + 1]}, p + 2 == q && PrimeQ[p*q - p - q] && PrimeQ[p*q + p + q]]; lst = {}; Do[ If[ fQ@n == True, AppendTo[lst, Prime@n]; Print@ Prime@n], {n, 39055}] (* _Robert G. Wilson v_, Mar 11 2007 *)
%Y Cf. A096342, A126148, A128547, A128548, A128550, A128551.
%K nonn
%O 1,1
%A _Zak Seidov_, Mar 10 2007
%E More terms from _Robert G. Wilson v_, Mar 11 2007
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