A023267 - OEIS

%I #18 Sep 08 2022 08:44:47

%S 7,11,19,61,97,107,131,181,251,271,397,401,419,467,557,601,677,727,

%T 907,929,1129,1297,1439,1481,1609,1699,1747,1901,1931,2027,2029,2099,

%U 2221,2267,2357,2377,2557,2617,2879,3001,3019,3121,3259,3371,3407,3457,3527

%N Primes that remain prime through 2 iterations of function f(x) = 9x + 8.

%C Primes p such that 9*p+8 and 81*p+80 are also primes. - _Vincenzo Librandi_, Aug 04 2010

%H John Cerkan, <a href="/A023267/b023267.txt">Table of n, a(n) for n = 1..10000</a>

%o (Magma) [n: n in [1..100000] | IsPrime(n) and IsPrime(9*n+8) and IsPrime(81*n+80)] // _Vincenzo Librandi_, Aug 04 2010

%Y Subsequence of A023235.

%K nonn

%O 1,1

%A _David W. Wilson_