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 A263617 #26 Apr 08 2025 13:57:32
%S A263617 4,7,15,20,31,37,56,70,95,113,162,193,264,310,415,486,640,741,950,
%T A263617 1082,1374,1556,1940,2176,2673,2975,3611,3994,4793,5268,6249,6827,
%U A263617 8028,8729
%N A263617 Number of numbers with at most n digits whose square is a palindrome.
%H A263617 G. J. Simmons, <a href="/A002778/a002778_2.pdf">Palindromic powers</a>, J. Rec. Math., 3 (No. 2, 1970), 93-98. [Annotated scanned copy]. See p. 95.
%t A263617 Table[Length[Select[Range[ 0, 10^n - 1], PalindromeQ[#^2] &]], {n, 6}] (* _Robert Price_, Apr 26 2019 *)
%Y A263617 Partial sums of A263616.
%Y A263617 Cf. A002778, A002779, A263618, A263619.
%K A263617 nonn,base,more
%O A263617 1,1
%A A263617 _N. J. A. Sloane_, Oct 23 2015
%E A263617 a(9)-a(10) from _Chai Wah Wu_, Oct 25 2015
%E A263617 a(11)-a(12) from _Michael S. Branicky_, May 23 2021
%E A263617 a(13)-a(22) (using A002778) from _Chai Wah Wu_, Sep 16 2021
%E A263617 a(23)-a(34) from _Max Alekseyev_, Apr 08 2025