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

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

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