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%I #32 Jul 22 2023 08:13:46
%S 12,13,21,31,33,99,102,103,112,113,122,201,211,221,301,311,1002,1003,
%T 1011,1012,1013,1021,1022,1031,1101,1102,1103,1112,1113,1121,1122,
%U 1201,1202,1211,1212,1301,2001,2011,2012,2021,2022,2101,2102,2111,2121
%N Roots of 'non-palindromic squares remaining square when written backwards'.
%C Those with trailing zeros are excluded.
%C Union of ordered entries of A106323 and A106324. - _Lekraj Beedassy_, May 02 2005
%H Jon E. Schoenfield, <a href="/A035123/b035123.txt">Table of n, a(n) for n = 1..8448</a> (first 798 terms from Seiichi Manyama; all terms < 10^10)
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/square.htm">Palindromic Squares</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>
%e 1212^2 = 1468944 -> 4498641 = 2121^2.
%t r[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Select[Range[2200], Mod[#, 10] != 0 && IntegerQ[Sqrt[r[#^2]]] && r[#^2] != #^2 &] (* _Jean-François Alcover_, Mar 08 2011 *)
%Y Cf. A035090, A035125.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Nov 15 1998