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 A075749 #26 Sep 08 2022 08:45:07 %S A075749 2,5,11,13,16,28,29,30,35,36,42,44,50,51,55,57,73,86,104,121,125,128, %T A075749 135,140,147,148,157,158,160,161,165,168,179,193,204,205,209,223,244, %U A075749 247,249,251,255,264,271,273,277,281,282,290,302,304,310,312,313,316 %N A075749 Numbers k such that 210*k +- 1 are twin primes. %H A075749 Amiram Eldar, <a href="/A075749/b075749.txt">Table of n, a(n) for n = 1..10000</a> %e A075749 k = 2 is a term since 210*2 - 1 = 419 and 210*2 + 1 = 421 are twin primes. %t A075749 Select[Range[6! ],PrimeQ[210*#-1]&&PrimeQ[210*#+1]&] (* _Vladimir Joseph Stephan Orlovsky_, Apr 08 2010 *) %o A075749 (PARI) isok(n) = isprime(210*n+1) && isprime(210*n-1); \\ _Michel Marcus_, Jan 14 2015 %o A075749 (Magma) [k:k in [1..320]| IsPrime(210*k-1) and IsPrime(210*k+1)]; // _Marius A. Burtea_, Jan 01 2020 %Y A075749 Cf. A002822 (with 6*k +- 1), A176114 (with 30*k +- 1). %K A075749 easy,nonn %O A075749 1,1 %A A075749 _Zak Seidov_, Oct 08 2002