A339504 Primes (p*(p+2)-2)/3 for p in A339503.

11, 47, 107, 587, 3467, 7499, 10799, 17327, 62207, 71147, 137387, 225227, 355007, 442367, 504299, 554699, 874799, 961067, 1175627, 1486847, 1512299, 1529387, 2617067, 2999999, 3525167, 3538187, 3629999, 4009007, 4148927, 4494527, 5116907, 5338667, 5467499, 8108207, 8227007, 10090667, 10156799

Offset

1,1

Comments

Primes of the form (p*(p+2)-2)/3 where p and p+2 are primes.

Primes q such that sqrt(3*q+3)-1 and sqrt(3*q+3)+1 are prime.

Links

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

Example

a(3)=107 is a term because 107=(17*19-2)/3 with 17, 17+2=19 and 107 all prime.

Maple

P:= {seq(ithprime(i), i=3..10000)}:
T:= P intersect map(`-`, P, 2):
select(isprime, map(p -> (p*(p+2)-2)/3, T));

Mathematica

Select[Map[(# (# + 2) - 2)/3 &, Select[Prime@ Range[3, 750], PrimeQ[# + 2] &]], PrimeQ] (* Michael De Vlieger, Dec 07 2020 *)

Crossrefs

Cf. A001359, A339503.

Sequence in context: A107149 A158463 A143830 * A178572 A036489 A076306

Adjacent sequences: A339501 A339502 A339503 * A339505 A339506 A339507

Keyword

nonn

Author

J. M. Bergot and Robert Israel, Dec 07 2020

Status

approved