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 A139191 #6 Jun 16 2014 08:06:23
%S A139191 1,39,1679,13305599,2075673599,118562476031999,40548366802943999,
%T A139191 8617338912961658879999,2947253997913233984847871999999,
%U A139191 2740946218059307605908520959999999,4587917697075448348771993193860300799999999,11150842204387935702723354017813583888383999999999,20138421021124611879118377356171332502421503999999999,86207747170389393547654785051203993323065877463039999999999,1424961094686675188099337917796466549896781262788937908223999999999999
%N A139191 Natural numbers of the form (prime(n)!-3)/3.
%F A139191 a(n)=(A139189(n+1)-2)/3. - _R. J. Mathar_, May 25 2008
%t A139191 Table[(Prime[n]! - 3)/3, {n, 2, 20}]
%Y A139191 Cf. A139189, A139190, A139191, A139192, A139193, A139194, A139195, A139196, A139197, A139198.
%K A139191 nonn
%O A139191 1,2
%A A139191 _Artur Jasinski_, Apr 11 2008
%E A139191 More terms from _R. J. Mathar_, May 25 2008