OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
a(n) >> n log^2 n. - Charles R Greathouse IV, Mar 17 2017
EXAMPLE
3 is in this sequence because 30*3^2 - 1 = 269 and 30*3^2 + 1 = 271 are twin primes.
MATHEMATICA
Select[Range@ 1431, PrimeQ[30*#^2 + 1] && PrimeQ[30*#^2 - 1] &] (* Indranil Ghosh, Mar 17 2017 *)
PROG
(Magma) [n: n in [1..1500] | IsPrime(30*n^2-1) and IsPrime(30*n^2+1)];
(PARI) is(n)=isprime(30*n^2-1) && isprime(30*n^2+1) \\ Charles R Greathouse IV, Mar 17 2017
(Python)
from sympy import isprime
[i for i in range(1, 1501) if isprime(30*i**2 - 1) and isprime(30*i**2 + 1)] # Indranil Ghosh, Mar 17 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Mar 17 2017
STATUS
approved