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A137137
Numbers k such that k and k^2 use only the digits 3, 6, 7, 8 and 9.
1
3, 6, 63, 83, 86, 833, 836, 876, 883, 887, 937, 8363, 8876, 8887, 8937, 9687, 9833, 9883, 79836, 79867, 93637, 96633, 96886, 98333, 98336, 98376, 98887, 798367, 798667, 936876, 936963, 937383, 968333, 986833, 988937, 989833, 989867, 993367, 998333, 998367, 7983667, 7987363, 7998336, 7998667, 8937387, 8938667, 9363637, 9366637, 9366786
OFFSET
1,1
COMMENTS
Generated with DrScheme.
LINKS
J. Wellons, Tables of Shared Digits [archived]
EXAMPLE
968968363768376^2 = 938899689983963839367377677376.
MATHEMATICA
With[{c={3, 6, 7, 8, 9}}, Table[Select[FromDigits/@Tuples[c, n], SubsetQ[c, IntegerDigits[#^2]]&], {n, 7}]]//Flatten (* Harvey P. Dale, Nov 18 2023 *)
CROSSREFS
Sequence in context: A219809 A137123 A137133 * A137134 A137090 A137138
KEYWORD
base,nonn
AUTHOR
Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
STATUS
approved