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 A256374 #22 Sep 08 2022 08:46:11
%S A256374 17,31,59,101,157,227,311,409,521,647,787,941,1109,1291,1487,1697,
%T A256374 2411,2677,2957,3251,3559,3881,4217,4567,4931,5309,5701,6961,8837,
%U A256374 9341,9859,10391,10937,11497,12071,12659,13877,15809,16481,17167,19309,20051,20807,21577,23159,23971
%N A256374 Primes of the form 7*k^2 + 7*k + 17.
%C A256374 The values k=0 through 15 all give primes.
%H A256374 Felix Fröhlich, <a href="/A256374/b256374.txt">Table of n, a(n) for n = 1..10000</a>
%e A256374 For k=15 we get 1697, a prime.
%e A256374 For k=16 we get 1921 = 17*113, not a prime, so not a term of the sequence.
%t A256374 Select[Table[7 n^2 + 7 n +17, {n, 0, 600}], PrimeQ]
%o A256374 (Magma) [ a: n in [0..200] | IsPrime(a) where a is 7*n^2 + 7*n + 17 ];
%o A256374 (PARI) for(k=0, 1e2, if(ispseudoprime(7*k^2+7*k+17), print1(7*k^2+7*k+17, ", "))) \\ _Felix Fröhlich_, Apr 01 2015
%Y A256374 Cf. A256375.
%K A256374 nonn,easy
%O A256374 1,1
%A A256374 _Avi Friedlich_, Mar 26 2015
%E A256374 Corrected by _Vincenzo Librandi_, Mar 27 2015
%E A256374 Edited by _N. J. A. Sloane_, Mar 27 2015