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 A076679 #24 Jun 24 2025 21:29:02 %S A076679 2,3,4,6,7,9,10,13,23,25,32,38,40,47,96,3442,4048,4522,4887,7033,9528, %T A076679 12915,31762,114482 %N A076679 Numbers k such that 3*k! + 1 is prime. %C A076679 a(25) > 115000. - _Serge Batalov_, Jun 15 2025 %e A076679 k = 6 is here because 3*6! + 1 = 2161 is prime. %o A076679 (PARI) isok(n) = isprime(3*n! + 1); \\ _Michel Marcus_, Nov 13 2016 %o A076679 (PFGW) ABC2 3*$a!+1 %o A076679 a: from 1 to 1000 // _Jinyuan Wang_, Feb 05 2020 %Y A076679 Cf. A002981, A051915, A076680, A076681, A076682, A076683, A178488, A180626, A126896. %K A076679 nonn,more %O A076679 1,1 %A A076679 Phillip L. Poplin (plpoplin(AT)bellsouth.net), Oct 25 2002 %E A076679 More terms from _Serge Batalov_, Feb 18 2015 %E A076679 a(20)-a(23) from _Roger Karpin_, Nov 13 2016 %E A076679 a(24) from _Serge Batalov_, Jun 15 2025