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 A141897 #20 Sep 08 2022 08:45:35 %S A141897 19,61,103,229,271,313,397,439,523,607,691,733,859,1069,1153,1237, %T A141897 1279,1321,1447,1489,1531,1657,1699,1741,1783,1867,1951,1993,2161, %U A141897 2203,2287,2371,2539,2707,2749,2791,2833,2917,3001,3169,3253,3463,3547,3631,3673 %N A141897 Primes congruent to 19 mod 21. %H A141897 Vincenzo Librandi, <a href="/A141897/b141897.txt">Table of n, a(n) for n = 1..1000</a> %F A141897 a(n) ~ 12n log n. - _Charles R Greathouse IV_, Jul 02 2016 %t A141897 Select[Range[19,5000,21],PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Apr 04 2011 *) %o A141897 (Magma) [ p: p in PrimesUpTo(5000) | p mod 21 eq 19 ]; // _Vincenzo Librandi_, Apr 05 2011 %o A141897 (PARI) is(n)=isprime(n) && n%21==19 \\ _Charles R Greathouse IV_, Jul 02 2016 %Y A141897 Cf. A000040, A124826. %K A141897 nonn,easy %O A141897 1,1 %A A141897 _N. J. A. Sloane_, Jul 11 2008