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A030487
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When squared gives number composed of digits {2, 5, 7}.
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3
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5, 15, 85, 165, 235, 1665, 15085, 16665, 166665, 268835, 1666665, 5076665, 16666665, 52683515, 165898335, 166666665, 278433515, 507668915, 850032485, 1508559835, 1666666665, 15085017485, 16666666665, 166666666665
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OFFSET
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1,1
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LINKS
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EXAMPLE
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5^2 = 25, so 5 is in the sequence.
15^2 = 225, so 15 is in the sequence.
25^2 = 625, which has a 2 and 5 but also a 6, so 25 is not in the sequence.
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MATHEMATICA
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Select[5Range[1, 9999, 2], Complement[IntegerDigits[#^2], {2, 5, 7}] == {} &] (* Alonso del Arte, Feb 25 2020 *)
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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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EXTENSIONS
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Extended and corrected by author 03/2000.
More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005
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STATUS
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approved
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