A340307 Primes of the form (p*q+r*s)/2, where p,q,r,s are consecutive primes.

89, 149, 233, 907, 3607, 6577, 13007, 20771, 27241, 34631, 72907, 84737, 110933, 145177, 213449, 360007, 463787, 680633, 746507, 1192469, 1695209, 2205233, 2643899, 3125959, 3261721, 4888547, 4995227, 5716897, 6095987, 6656483, 7225349, 7734029, 7868027, 7969439, 8071307, 11189053, 11329991

Offset

1,1

Links

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

Example

a(3) = 233 is a term because 233 = (11*13+17*19)/2.

Maple

q:= 3: r:= 5: s:= 7:
count:= 0: R:= NULL:
while count < 100 do
  p:= q; q:= r; r:= s; s:= nextprime(s);
  v:= (p*q + r*s)/2;
  if isprime(v) then count:= count+1; R:= R, v fi
od:
R;

Crossrefs

Cf. A340308.

Sequence in context: A141938 A267819 A031416 * A353249 A247114 A075589

Adjacent sequences: A340304 A340305 A340306 * A340308 A340309 A340310

Keyword

nonn

Author

J. M. Bergot and Robert Israel, Jan 03 2021

Status

approved