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 A046409 #11 Oct 10 2019 22:43:13 %S A046409 66,606,2222,2882,3333,5555,6886,7777,26462,39693,145541,167761, %T A046409 226622,248842,339933,347743,662266,664466,668866,682286,993399, %U A046409 996699,2080802,2284822,6080806,6264626,9396939,11444411,11666611,11777711 %N A046409 Palindromes with exactly 3 distinct palindromic prime factors. %H A046409 Chai Wah Wu, <a href="/A046409/b046409.txt">Table of n, a(n) for n = 1..1000</a> %Y A046409 Cf. A046329, A046377. %K A046409 nonn,base %O A046409 1,1 %A A046409 _Patrick De Geest_, Jun 15 1998