%I
%S 11,61,251,397,467,727,907,1747,1901,2221,2617,3121,3527,3581,4001,
%T 4099,4211,4759,5231,5717,6277,6661,6689,7237,7877,8117,8171,8581,
%U 9371,9587,11171,12457,12539,13109,14221,15187,15731,16069,16477,16979,17117,17491
%N Numbers n such that n remains prime through 3 iterations of function f(x) = 9x + 8.
%C n, 9*n+8, 81*n+80, 729*n+728 are primes.  _Vincenzo Librandi_, Aug 04 2010
%H John Cerkan, <a href="/A023298/b023298.txt">Table of n, a(n) for n = 1..10000</a>
%o (MAGMA) [n: n in [1..450000]  IsPrime(n) and IsPrime(9*n+8) and IsPrime(81*n+80) and IsPrime(729*n+728)] // _Vincenzo Librandi_, Aug 04 2010
%Y Subsequence of A023235 and A023267.
%K nonn
%O 1,1
%A _David W. Wilson_
