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A058422
Squares composed of digits {0,1,8}, not ending with zero.
3
1, 81, 11881, 811801, 1018081, 81018001, 100180081, 108180801, 8100180001, 10001800081, 10181011801, 810001800001, 1000018000081, 1008018008001, 80181118180881, 81000018000001, 100000180000081, 100180101018001, 1180000888001881, 8100000180000001, 10000001800000081
OFFSET
1,2
COMMENTS
Includes all numbers of the forms (10^k + 9)^2, (9*10^k + 1)^2, (100^k + 4*10^k + 1)^2, and (10*100^k + 9*10^k + 1)^2 for k >= 2. - Andrew Howroyd, Oct 18 2024
LINKS
FORMULA
a(n) = A058421(n)^2. - Andrew Howroyd, Oct 18 2024
MATHEMATICA
Select[FromDigits/@Tuples[{0, 1, 8}, 17], Mod[#, 10]!=0&&IntegerQ[Sqrt[#]]&] (* Harvey P. Dale, Sep 09 2022 *)
CROSSREFS
Cf. A058421.
Sequence in context: A017020 A237027 A185847 * A053913 A053895 A053905
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Nov 15 2000
STATUS
approved