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A136984
Numbers k such that k and k^2 use only the digits 1, 2, 3, 8 and 9.
1
1, 3, 9, 11, 91, 111, 139, 911, 1389, 1823, 1839, 1983, 2983, 9123, 18391, 31339, 93989, 181339, 199823, 299823, 313339, 313391, 913139, 939889, 1811983, 1813339, 1983233, 2883123, 2981339, 2983139, 9122983, 9393239, 11128339, 11323833, 13828923, 13889323, 13921889, 18393989, 19833891, 19983323, 19998233, 19998323, 29813391, 29818333
OFFSET
1,2
COMMENTS
Generated with DrScheme.
LINKS
J. Wellons, Tables of Shared Digits [archived]
EXAMPLE
198298292829823^2 = 39322212939222231813238211329.
MATHEMATICA
With[{c={1, 2, 3, 8, 9}}, Select[Flatten[Table[FromDigits/@Tuples[c, n], {n, 8}]], SubsetQ[c, IntegerDigits[#^2]]&]] (* Harvey P. Dale, Jan 11 2019 *)
CROSSREFS
Sequence in context: A069871 A375098 A061957 * A168400 A310318 A310319
KEYWORD
base,nonn
AUTHOR
Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
STATUS
approved