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%I #21 Apr 24 2022 02:32:39
%S 1,4,9,144,196,625,11664,14884,46656,96100,1493284,4112784,6385729,
%T 9253764,139287204,149377284,187799616,618268225,634284225,678758809,
%U 929884036,14938217284,43325589904,61076696769,97482577284
%N Squares which when digits are rotated left once remain square.
%C Those resulting in leading zeros are excluded.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>
%e 2527^2 = 6385729 -> 3857296 = 1964^2.
%t okQ[n_]:=Module[{idn=IntegerDigits[n]},idn[[2]]!=0&&IntegerQ[Sqrt[ FromDigits[RotateLeft[idn]]]]]; Join[{1,4,9},Select[Range[4,320000]^2, okQ]] (* _Harvey P. Dale_, Apr 30 2011 *)
%o (Python)
%o from itertools import count, islice
%o from sympy.solvers.diophantine.diophantine import diop_DN
%o def A035127_gen(): # generator of terms
%o for l in count(0):
%o l1, l2 = 10**(l+1), 10**l
%o yield from sorted(set(y**2 for z in (diop_DN(10,m*(1-l1)) for m in range(10)) for x, y in z if l1 >= x**2 >= l2))
%o A035127_list = list(islice(A035127_gen(),20)) # _Chai Wah Wu_, Apr 23 2022
%Y Subsequence of A000290.
%Y Cf. A045878, A035131.
%K nonn,base
%O 1,2
%A _Patrick De Geest_, Nov 15 1998