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 A049985 #19 Jun 11 2025 09:47:54
%S A049985 3,17,599,35279,322559,439084799,293999475161295508340735999999
%N A049985 Primes of form k! - (k-1)! - 1.
%C A049985 The next term has 116 digits. - _Harvey P. Dale_, Feb 17 2015
%t A049985 f[n_]:=n!-n; lst={};Do[If[PrimeQ[f[n+1]-f[n]],AppendTo[lst,f[n+1]-f[n]]],{n,0,5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jun 27 2009 *)
%t A049985 Select[#[[2]]-#[[1]]-1&/@Partition[Range[100]!,2,1],PrimeQ] (* _Harvey P. Dale_, Feb 17 2015 *)
%Y A049985 Cf. A049433 (corresponding k), A090704.
%K A049985 nonn
%O A049985 1,1
%A A049985 _N. J. A. Sloane_