A374613 - OEIS

%I #12 Jul 25 2024 15:20:11

%S 29,71,73,79,83,127,131,137,167,173,193,197,211,223,229,233,239,251,

%T 269,331,347,349,373,419,421,431,433,439,457,467,487,503,509,541,563,

%U 577,587,619,641,647,653,659,661,691,719,727,733,743,751,797,809,811,821,829,839,853,859,863,887

%N Prime numbers p with the property that neither of 2*(p+next prime to p)+/-1 is prime.

%C Conjecture: this sequence is infinite.

%e 2 is not a term because 2*(2+3)+1=11 is a prime.

%e 5 is not a term because 2*(5+7)-1=23 is a prime.

%e 29 is a term because neither 2(29+31)+1 nor 2(29+31)-1 is a prime.

%t Prime[Select[Range[155], !PrimeQ[2(Prime[#]+Prime[#+1])-1] && !PrimeQ[2(Prime[#]+Prime[#+1])+1]&]] (* _Stefano Spezia_, Jul 15 2024 *)

%K nonn

%O 1,1

%A _Marcin Barylski_, Jul 14 2024