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%I #12 Jul 25 2021 20:42:46
%S 0,1,2,3,11,22,26,101,111,121,202,212,264,307,1001,1111,2002,2285,
%T 2636,10001,10101,10201,11011,11111,11211,20002,20102,22865,24846,
%U 30693,100001,101101,110011,111111,200002,1000001,1001001,1002001,1010101,1011101,1012101
%N Numbers k such that k^2 is a palindrome with an odd number of digits.
%H P. De Geest, <a href="http://www.worldofnumbers.com/subsquar.htm">Subsets of Palindromic Squares</a>
%t id[n_]:=IntegerDigits[n]; palQ[n_]:=FromDigits[Reverse[id[n]]]==n; t={}; Do[If[palQ[x=n^2] && OddQ[Length[id[x]]], AppendTo[t,n]],{n,1012102}]; t (* _Jayanta Basu_, May 13 2013 *)
%Y Cf. A028817.
%K nonn,base
%O 1,3
%A _Patrick De Geest_
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