OFFSET
1,1
LINKS
K. D. Bajpai, Table of n, a(n) for n = 1..11485
EXAMPLE
a(2) = 29 is prime: 2*29^3 + 1 = 48779 and 2*29^3 + 3 = 48781 are both primes.
a(3) = 1709 is prime: 2*1709^3 + 1 = 9982887659 and 2*1709^3 + 3 = 9982887661 are both primes.
MATHEMATICA
Select[Prime[Range[10000]], And[PrimeQ[2*#^3 + 1], PrimeQ[2*#^3 + 3]] &]
Select[Prime[Range[7500]], AllTrue[2#^3+{1, 3}, PrimeQ]&] (* Harvey P. Dale, Apr 03 2023 *)
PROG
(PARI) s=[]; forprime(p=2, 10^5, if(isprime(2*p^3 + 1) && isprime(2*p^3 + 3), s=concat(s, p))); s
CROSSREFS
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Dec 13 2014
STATUS
approved