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 A104048 #11 Jan 21 2024 09:24:05
%S A104048 0,20,30,50,60,80,90,120,140,170,200,210,230,270,300,360,380,410,540,
%T A104048 590,620,650,690,710,750,840,860,870,900,980,1080,1130,1200,1220,1260,
%U A104048 1290,1310,1460,1470,1490,1500,1560,1620,1640,1770,1820,1880,1890,2010,2030,2100,2220,2240,2270
%N A104048 Numbers k such that k11 is prime and k is a multiple of ten.
%e A104048 20 is a term because it is a multiple of 10 and 2011 is a prime.
%e A104048 170 is a term because it is a multiple of 10 and 17011 is a prime.
%e A104048 360 is a term because it is a multiple of 10 and 36011 is a prime.
%t A104048 Select[Range[0,2270,10],PrimeQ[FromDigits[Prepend[{1,1},#]]]&] (* _James C. McMahon_, Jan 20 2024 *)
%Y A104048 Cf. A101471.
%K A104048 base,nonn
%O A104048 1,2
%A A104048 _Parthasarathy Nambi_, Mar 01 2005