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 A096097 #14 Nov 30 2019 02:05:12 %S A096097 2,1,3,71,7,10177,2100001,101770000001,4603,13,107,4013,23, %T A096097 3097349301044927552199565217412468305904367,1847,37,367767021959, %U A096097 54371,3229,17,520063,29,389,8059,732713,11,7123120001,137,294563,1656881076199062425029,313583,4817,277 %N A096097 a(1) = 2, a(2) = 1; for n >= 3, a(n) = least prime not included earlier that divides the concatenation of all previous terms. %C A096097 Conjecture:(1) Every concatenation is squarefree. (2) This is a rearrangement of the noncomposite numbers other than 5. %C A096097 Conjecture (1) is false. 3^2 divides the concatenation for a(22) and a(30). - _Sean A. Irvine_, Nov 25 2009 %e A096097 a(4) = 71 as 213 = 3*71. %Y A096097 Cf. A096098. %K A096097 base,nonn %O A096097 1,1 %A A096097 _Amarnath Murthy_, Jun 24 2004 %E A096097 More terms from _Sean A. Irvine_, Nov 25 2009 %E A096097 a(30)-a(33) from _Chai Wah Wu_, Nov 29 2019