This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A023298 #22 Aug 28 2024 14:47:36 %S A023298 11,61,251,397,467,727,907,1747,1901,2221,2617,3121,3527,3581,4001, %T A023298 4099,4211,4759,5231,5717,6277,6661,6689,7237,7877,8117,8171,8581, %U A023298 9371,9587,11171,12457,12539,13109,14221,15187,15731,16069,16477,16979,17117,17491 %N A023298 Primes that remain prime through 3 iterations of function f(x) = 9x + 8. %C A023298 Primes p such that 9*p+8, 81*p+80, and 729*p+728 are also primes. - _Vincenzo Librandi_, Aug 04 2010 %H A023298 John Cerkan, <a href="/A023298/b023298.txt">Table of n, a(n) for n = 1..10000</a> %o A023298 (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 A023298 Subsequence of A023235 and A023267. %K A023298 nonn %O A023298 1,1 %A A023298 _David W. Wilson_