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 A152213 #8 Dec 03 2017 12:02:52 %S A152213 0,1,2,9,66,164,221,224,2058,3224,12284,13457,22277,22761,83381 %N A152213 Numbers n such that 7^n + 12 is prime. %C A152213 a(16) > 10^5. - _Robert Price_, Jan 24 2014 %t A152213 Select[Range[0,84000],PrimeQ[7^#+12]&] (* _Harvey P. Dale_, Dec 03 2017 *) %o A152213 (PARI) is(n)=ispseudoprime(7^n+12) \\ _Charles R Greathouse IV_, Feb 17 2017 %Y A152213 Cf. A236371, A217131, A191469, A090669, A096305, A217130, A217132, A152213. %K A152213 nonn,more %O A152213 1,3 %A A152213 Huseyin Azoguz (huseyin(AT)mmnetz.de), Nov 29 2008 %E A152213 a(11)-a(15) from _Robert Price_, Jan 24 2014