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%I #30 May 22 2022 00:01:01
%S 1,2,3,11,12,13,21,22,26,31,33,99,101,102,103,111,112,113,121,122,201,
%T 202,211,212,221,264,301,307,311,836,1001,1002,1003,1011,1012,1013,
%U 1021,1022,1031,1101,1102,1103,1111,1112,1113,1121,1122,1201,1202,1211
%N Roots of 'squares remaining square when written backwards'.
%C Numbers with trailing zeros are excluded.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>
%H <a href="/index/Sq#sqrev">Index entry for sequences related to reversing digits of squares</a>
%F a(n) = sqrt(A033294(n)). - _Michel Marcus_, Sep 22 2015
%e 99^2 = 9801 -> 1089 = 33^2.
%t Select[Range[10000], IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[ #^2]]]]] &] (* and then delete terms ending with 0 - _N. J. A. Sloane_, Jul 08 2011 *)
%t Sqrt[Select[Range[2000]^2, Mod[#, 10]!=0&&IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[#]]]]]&]] (* _Vincenzo Librandi_, Sep 22 2015 *)
%Y Cf. A033294, A035125.
%K nonn,base
%O 1,2
%A _Patrick De Geest_, Nov 15 1998
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