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A136997
Numbers k such that k and k^2 use only the digits 1, 2, 4, 7 and 8.
1
1, 2, 11, 12, 21, 22, 28, 88, 122, 221, 278, 418, 421, 471, 472, 478, 1478, 1488, 2778, 2878, 4141, 4271, 4721, 8472, 8878, 11141, 14771, 21171, 21778, 27771, 27878, 84722, 88418, 88471, 112778, 112878, 118818, 211488, 272841, 277818, 287771, 414418, 422222, 477778, 878221, 884428, 1128222, 1214171, 1477221, 1477421, 2174278, 2178818, 2184441
OFFSET
1,2
COMMENTS
Generated with DrScheme.
LINKS
J. Wellons, Tables of Shared Digits [archived]
EXAMPLE
847184817428412^2 = 717722114881211772824744841744.
CROSSREFS
Sequence in context: A065020 A136986 A096109 * A085184 A037089 A038118
KEYWORD
base,nonn
AUTHOR
Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
STATUS
approved