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%I A227907 #21 Jun 22 2020 23:30:58
%S A227907 2,3,5,7,11,19,37,67,71,79,137,191,229,277,283,317,347,359,397,409,
%T A227907 431,457,461,479,499,577,691,739,743,757,787,811,829,839,967,1009,
%U A227907 1061,1087,1091,1109,1153,1193,1279,1327,1373,1429
%N A227907 Primes p such that 4*p - q is also prime, where p, q are consecutive primes.
%H A227907 Robert Israel, <a href="/A227907/b227907.txt">Table of n, a(n) for n = 1..10000</a>
%p A227907 isA227907 := proc(n)
%p A227907     local q;
%p A227907     if isprime(n) then
%p A227907         q := nextprime(n) ;
%p A227907         isprime(4*n-q) ;
%p A227907     else
%p A227907         false;
%p A227907     end if;
%p A227907 end proc:
%p A227907 for n from 1 to 3000 do
%p A227907     if isA227907(n) then
%p A227907         printf("%d,",n) ;
%p A227907     end if;
%p A227907 end do: # _R. J. Mathar_, Oct 14 2013
%o A227907 (PARI) isokp(p) = isprime(p) && isprime(4*p - nextprime(p+1)); \\ _Michel Marcus_, Oct 13 2013
%K A227907 nonn
%O A227907 1,1
%A A227907 _Irina Gerasimova_, Oct 12 2013

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