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A030487
When squared gives number composed of digits {2, 5, 7}.
3
5, 15, 85, 165, 235, 1665, 15085, 16665, 166665, 268835, 1666665, 5076665, 16666665, 52683515, 165898335, 166666665, 278433515, 507668915, 850032485, 1508559835, 1666666665, 15085017485, 16666666665, 166666666665
OFFSET
1,1
EXAMPLE
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.
MATHEMATICA
Select[5Range[1, 9999, 2], Complement[IntegerDigits[#^2], {2, 5, 7}] == {} &] (* Alonso del Arte, Feb 25 2020 *)
CROSSREFS
Cf. A030485.
Sequence in context: A088935 A183937 A275971 * A165470 A165625 A058820
KEYWORD
nonn,base
EXTENSIONS
Extended and corrected by author 03/2000.
More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005
STATUS
approved