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A137020 Numbers k such that k and k^2 use only the digits 1, 2, 8 and 9. 0
1, 9, 11, 91, 911 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Generated with DrScheme.

No additional terms through 10^10. - Harvey P. Dale, Jul 04 2012

LINKS

Table of n, a(n) for n=1..5.

J. Wellons, Tables of Shared Digits

EXAMPLE

911^2 = 829921.

MATHEMATICA

okQ[n_]:=Module[{u=Union[IntegerDigits[n^2]]}, And@@Table[MemberQ[ {1, 2, 8, 9}, u[[i]]], {i, Length[u]}]]; Flatten[Table[ Select[FromDigits/@ Tuples[{1, 2, 8, 9}, x], okQ], {x, 10}]] (* Harvey P. Dale, Jul 04 2012 *)

CROSSREFS

Sequence in context: A289288 A137016 A053886 * A058304 A027727 A019328

Adjacent sequences:  A137017 A137018 A137019 * A137021 A137022 A137023

KEYWORD

base,nonn

AUTHOR

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

STATUS

approved

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Last modified October 22 13:49 EDT 2021. Contains 348170 sequences. (Running on oeis4.)