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A207373
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Numbers whose square is the product of a number and its reverse.
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2
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252, 403, 504, 660, 816, 2772, 3267, 4356, 20502, 22932, 23632, 25452, 26962, 27972, 31003, 32967, 35143, 41004, 43956, 45864, 48384, 48616, 55242, 58422, 66976, 75525, 225522, 252252, 259952, 279972, 329967, 341033, 403403, 439956, 451044, 504504, 619916
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OFFSET
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1,1
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COMMENTS
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Number and its reverse must have the same number of digits.
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LINKS
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EXAMPLE
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35143^2 = 96721*12769.
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MATHEMATICA
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nir[n_]:=If[PalindromeQ[n]||Divisible[n, 10], 0, n IntegerReverse[n]]; Sqrt[#] &/@ Select[Array[nir, 500000], #!=0&&IntegerQ[Sqrt[#]]&]//Union (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 12 2017 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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