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 A263994 #12 Jan 31 2017 01:06:19 %S A263994 21,1041,1051,1061,1071,1081,1091,107209,108429,109803,10715097, %T A263994 10854691,10904639,10904731,10904731,10904731,10904731,10983831, %U A263994 11002311,11002311,11002311,1078112970,1078122970 %N A263994 First element of first run of at least n consecutive numbers not representable as the sum of two base-10 palindromes. %C A263994 First occurrence of n consecutive numbers in A035137. %H A263994 Hugo Pfoertner, <a href="/A263994/b263994.txt">Table of n, a(n) for n = 1..52</a>. Checked up to 2*10^11. %e A263994 a(2)=1041 because 1041 and 1042 are the first two consecutive numbers in A035137. %Y A263994 Cf. A002113, A035137, A260255. %K A263994 nonn,base %O A263994 1,1 %A A263994 _Hugo Pfoertner_, Oct 31 2015