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A216481
a(n) is the least multiple of n which uses only digit 2, or a(n) = -1 if no such multiple exists.
2
2, 2, 222, -1, -1, 222, 222222, -1, 222222222, -1, 22, -1, 222222, 222222, -1, -1, 2222222222222222, 222222222, 222222222222222222, -1, 222222, 22, 2222222222222222222222, -1, -1, 222222, 222222222222222222222222222, -1, 2222222222222222222222222222, -1, 222222222222222, -1, 222222, 2222222222222222, -1, -1, 222, 222222222222222222, 222222, -1, 22222, 222222
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Table of n, a(n) for n=1..42.
CROSSREFS
Cf. A004290, A078241, A079339, A181060, A181061, A216812.
Sequence in context: A100956 A358621 A304915 * A078241 A216812 A068103
Adjacent sequences: A216478 A216479 A216480 * A216482 A216483 A216484
KEYWORD
sign,base
AUTHOR
V. Raman, Sep 07 2012
STATUS
approved

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Last modified September 29 15:18 EDT 2024. Contains 376322 sequences.
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