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 A029983 #17 Feb 10 2025 19:55:39 %S A029983 0,1,9,20457529,143784081,331130809,20074072489,1193532215121, %T A029983 10036851273801,41413201925481,155991531977649,320642706437001, %U A029983 4665141483989281,87463589042698969,152191954834044129 %N A029983 Squares which are palindromes in base 2. %H A029983 Chai Wah Wu, <a href="/A029983/b029983.txt">Table of n, a(n) for n = 1..22</a> %H A029983 Patrick De Geest, <a href="https://www.worldofnumbers.com/nobase10pg2.htm">Palindromic Squares in bases 2 to 17</a> %H A029983 G. J. Simmons, <a href="/A002778/a002778.pdf">On palindromic squares of non-palindromic numbers</a>, J. Rec. Math., 5 (No. 1, 1972), 11-19. [Annotated scanned copy] %o A029983 (Python) %o A029983 from itertools import count, islice %o A029983 def A029983_gen(): # generator of terms %o A029983 return filter(lambda k: (s:=bin(k)[2:])[:(t:=(len(s)+1)//2)]==s[:-t-1:-1],(k**2 for k in count(0))) %o A029983 A029983_list = list(islice(A029983_gen(),10)) # _Chai Wah Wu_, Jun 23 2022 %Y A029983 Cf. A003166. %K A029983 nonn,base %O A029983 1,3 %A A029983 _Patrick De Geest_