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A137042
Numbers k such that k and k^2 use only the digits 1, 3, 6 and 9.
0
1, 3, 6, 13, 19, 31, 63, 369, 31131, 969119
OFFSET
1,2
COMMENTS
Generated with DrScheme.
LINKS
EXAMPLE
969119^2 = 939191636161.
MATHEMATICA
With[{c={1, 3, 6, 9}}, Table[Select[FromDigits/@Tuples[c, n], SubsetQ[c, IntegerDigits[ #^2]]&], {n, 6}]]//Flatten (* Harvey P. Dale, Nov 17 2018 *)
CROSSREFS
Sequence in context: A263621 A137039 A137035 * A080546 A080554 A259583
KEYWORD
base,nonn,more
AUTHOR
Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
STATUS
approved