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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
211, 773, 797, 929, 1733, 2113, 2417, 2531, 2621, 2663, 2671, 3041, 3307, 3491, 3499, 4099, 4397, 4423, 4567, 4583, 4987, 5483, 5743, 6101, 6841, 6899, 7187, 7309, 7417, 7529, 9649, 10103, 10463, 10501, 10607, 10631, 10651, 11003, 11119, 11833, 11941, 12479, 12763, 12967, 13163, 13697, 14449 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

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

MAPLE

R:= NULL: count:= 0:

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

while count < 100 do

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

  if isprime((q*r-p*s)/2) then

     count:= count+1; R:= R, p;

  fi

od:

R;

CROSSREFS

Cf. A342505, A342506, A342509.

Sequence in context: A137770 A142761 A308798 * A104299 A032632 A241959

Adjacent sequences:  A342505 A342506 A342507 * A342509 A342510 A342511

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Mar 14 2021

STATUS

approved

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Last modified September 26 03:46 EDT 2021. Contains 347664 sequences. (Running on oeis4.)