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 A247166 #48 Sep 26 2022 05:28:33 %S A247166 0,1,2,7,10,39,42,201,225,551 %N A247166 Numbers k such that 15^k+4 is prime. %C A247166 No further terms up to 10000. %C A247166 No further terms up to 10^5. - _Tyler NeSmith_, Jan 21 2021 %t A247166 a247166[n_Integer] := Select[Range[n], PrimeQ[15^# + 4] &]; a247166[10^4] (* _Michael De Vlieger_, Dec 03 2014 *) %o A247166 (PARI) for(n=0, 1e5, if(ispseudoprime(15^n+4), print1(n, ", "))) %o A247166 (Magma) [n: n in [0..300] | IsPrime(15^n+4)]; // _Vincenzo Librandi_, Dec 01 2015 %Y A247166 Corresponding sequences for m^k+4: A058958 (m=3), A124621 (m=5), A096305 (m=7), A217384 (m=9), A137236 (m=13), A243397 (m=19). %K A247166 nonn,more %O A247166 1,3 %A A247166 _Felix Fröhlich_, Dec 01 2014 %E A247166 Offset changed to 1 by _Georg Fischer_, Sep 26 2022