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A342508 Primes p such that (q*r-p*s)/2 is prime, where p,q,r,s are consecutive primes. 5

%I

%S 211,773,797,929,1733,2113,2417,2531,2621,2663,2671,3041,3307,3491,

%T 3499,4099,4397,4423,4567,4583,4987,5483,5743,6101,6841,6899,7187,

%U 7309,7417,7529,9649,10103,10463,10501,10607,10631,10651,11003,11119,11833,11941,12479,12763,12967,13163,13697,14449

%N Primes p such that (q*r-p*s)/2 is prime, where p,q,r,s are consecutive primes.

%H Robert Israel, <a href="/A342508/b342508.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3) = 797 is a term because 797, 809, 811, 821 are consecutive primes with (809*811-797*821)/2 = 881 prime.

%p R:= NULL: count:= 0:

%p q:= 3: r:= 5: s:= 7:

%p while count < 100 do

%p p:= q; q:= r; r:= s; s:= nextprime(s);

%p if isprime((q*r-p*s)/2) then

%p count:= count+1; R:= R, p;

%p fi

%p od:

%p R;

%Y Cf. A342505, A342506, A342509.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Mar 14 2021

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Last modified October 20 16:07 EDT 2021. Contains 348111 sequences. (Running on oeis4.)