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Primes in A114381.
1

%I #9 Jun 08 2021 14:57:41

%S 23,41,109,373,349,991,839,991,2689,2081,1667,3037,2357,4889,12253,

%T 3631,16361,7121,5197,12347,9011,5501,29663,10211,32341,15727,7039,

%U 13127,13669,15427,28807,16249,9829,31019,31849,25321,60101,33871,34361,14813,64783,28201,40099,69011,19073,19973,101287

%N Primes in A114381.

%H Robert Israel, <a href="/A345099/b345099.txt">Table of n, a(n) for n = 1..10000</a>

%e A114381(2), A114381(3) and A114381(5) = 109 are prime while A114381(1) and A114382(4) are not, so a(3) = 109.

%p P:= [seq(ithprime(i),i=1..10000)]:

%p f:= n -> convert(P[P[n]..P[n+1]],`+`):

%p select(isprime, map(f, [$1..numtheory:-pi(10000)-1]));

%t Select[Array[Sum[Prime[n],{n,Prime[#],Prime[#+1]}]&,200],PrimeQ] (* _Giorgos Kalogeropoulos_, Jun 08 2021 *)

%Y Cf. A114381.

%K nonn,look

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Jun 07 2021