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%I #11 Oct 13 2020 15:57:39
%S 1,4,9,100,121,144,169,400,441,484,676,900,961,1521,1681,1764,4624,
%T 4761,5625,9409,10000,10201,10404,10609,11881,12321,14161,14641,16641,
%U 17161,19321,19881,40000,40401,40804,41209,43264,44944,47524,49284
%N Squares with property that swapping first and last digits also gives a square.
%H Harvey P. Dale, <a href="/A069707/b069707.txt">Table of n, a(n) for n = 1..1000</a>
%e 1764 and 4761 both are squares hence both are members.
%t Do[t = IntegerDigits[n^2]; u = t; u[[1]] = t[[ -1]]; u[[ -1]] = t[[1]]; t = FromDigits[u]; If[ IntegerQ[ Sqrt[t]], Print[n^2]], {n, 1, 300}]
%t sfldQ[n_]:=Module[{idn=IntegerDigits[n]},IntegerQ[Sqrt[FromDigits[Join[ {idn[[-1]]},Most[ Rest[idn]],{idn[[1]]}]]]]]; Join[{1,4,9},Select[ Range[10,250]^2,sfldQ]] (* _Harvey P. Dale_, Oct 13 2020 *)
%Y Cf. A069706, A069708.
%K nonn,base
%O 1,2
%A _Amarnath Murthy_, Apr 08 2002
%E Edited and extended by _Robert G. Wilson v_
%E Edited by _N. J. A. Sloane_, Jan 20 2009
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