OFFSET
1,1
COMMENTS
All terms are obviously odd.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
25 is a term because (25^2 - 3)/2 = 311 and (25^2 + 1)/2 = 313 are twin primes.
MAPLE
filter:= n -> isprime((n^2-3)/2) and isprime((n^2+1)/2):
select(filter, [seq(i, i=1..2000, 2)]); # Robert Israel, Apr 24 2017
MATHEMATICA
Select[Range[1, 1285, 2], Times @@ Boole@ Map[PrimeQ, (#^2 + {-3, 1})/2] == 1 &] (* Michael De Vlieger, Mar 28 2017 *)
PROG
(Sage) [n for n in range(3, 1700, 2) if is_prime((n^2 - 3)//2) and is_prime((n^2 + 1)//2)]
(PARI) isok(n) = isprime((n^2 - 3)/2) && isprime((n^2 + 1)/2); \\ Michel Marcus, Apr 04 2017
(Python)
from sympy import isprime
print([n for n in range(3, 1700, 2) if isprime((n**2 - 3)//2) and isprime((n**2 + 1)//2)]) # Indranil Ghosh, Apr 04 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Giuseppe Coppoletta, Mar 27 2017
STATUS
approved