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 A124083 #14 Oct 01 2024 11:24:14 %S A124083 1,2,3,60,90 %N A124083 Numbers k such that prime(k)!/prime(k)# + 1 is prime. %C A124083 a(6) > 500 if it exists. - _Felix Fröhlich_, Sep 15 2019 %C A124083 a(6) > 2500 if it exists. - _Michael S. Branicky_, Oct 01 2024 %e A124083 1*2/2 +1 = 2 prime so a(1)=1 as 2=prime(1). %e A124083 1*2*3/(2*3) +1 = 2 prime so a(2)=2 as 3=prime(2). %e A124083 1*2*3*4*5/(2*3*5) +1 = 5 prime so a(3)=3 as 5=prime(3). %o A124083 (PARI) isok(k) = isprime(prime(k)!/prod(i=1, k, prime(i)) + 1); \\ _Michel Marcus_, Sep 15 2019 %Y A124083 Cf. A092435 (p!/p#), A124082. %K A124083 nonn,more %O A124083 1,2 %A A124083 _Pierre CAMI_, Nov 25 2006