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A136915
Numbers k such that k and k^2 use only the digits 0, 2, 5 and 7.
1
0, 5, 50, 500, 505, 755, 5000, 5005, 5050, 7550, 50000, 50005, 50050, 50500, 50505, 75500, 500000, 500005, 500050, 500500, 500505, 500755, 505000, 505050, 755000, 5000000, 5000005, 5000050, 5000500, 5000505, 5000755, 5005000, 5005005, 5005050, 5007550, 5025505, 5050000, 5050005, 5050500, 7550000, 7550005, 50000000, 50000005, 50000050
OFFSET
1,2
COMMENTS
Generated with DrScheme.
LINKS
J. Wellons, Tables of Shared Digits [archived]
EXAMPLE
505050250050005^2 = 255075755075572575505000500025.
CROSSREFS
Sequence in context: A266028 A228751 A299868 * A136918 A136910 A267663
KEYWORD
base,nonn
AUTHOR
Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
STATUS
approved