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 A089953 #14 Jan 21 2020 19:45:54 %S A089953 0,2,4,8,10,12,18,20,22,24,30,32,34,40,44,48,50,52,58,62,64,68,72,74, %T A089953 78,88,90,92,100,102,108,110,114,120,122,124,130,134,138,142,144,150, %U A089953 152,160,164,172,178,180,188,190,198,200,202,204,208,212,218,222,228 %N A089953 Numbers n such that 3*n+7 is prime. %D A089953 M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988. %D A089953 Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997. %H A089953 Daniel Starodubtsev, <a href="/A089953/b089953.txt">Table of n, a(n) for n = 1..10000</a> %F A089953 a(n) = A034936(n)-1 = A024892(n)-2 = 2*A024899(n)-2. %o A089953 (PARI) is(n)=isprime(3*n+7) \\ _Charles R Greathouse IV_, May 22 2017 %Y A089953 Cf. A002476 gives primes, A034936, A024892, A024899. %K A089953 nonn %O A089953 1,2 %A A089953 _Giovanni Teofilatto_, Jan 12 2004 %E A089953 Offset corrected by _Arkadiusz Wesolowski_, Aug 09 2011