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 A083832 #10 Apr 06 2017 12:07:15
%S A083832 5,9,33,353,525,565,929,969,3553,35553,52125,52525,52925,56165,56565,
%T A083832 56965,92129,92529,92929,96169,96569,96969,355553,3555553,5212125,
%U A083832 5216125,5252525,5256525,5292925,5296925,5612165,5616165,5652565
%N A083832 Palindromes of the form 4n + 1 where n is also a palindrome. Palindromes arising in A083831.
%t A083832 4#+1&/@Select[Range[1500000],AllTrue[{#,4#+1},PalindromeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Apr 06 2017 *)
%Y A083832 Cf. A083829, A083830, A083831.
%K A083832 base,nonn
%O A083832 1,1
%A A083832 _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 09 2003
%E A083832 Corrected and extended by _Ray Chandler_, May 21 2003