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A244927
Least positive number k such that k*n written in base 10 is either a repunit or of the form 1111....0000.
1
1, 5, 37, 25, 2, 185, 15873, 125, 12345679, 1, 1, 925, 8547, 79365, 74, 625, 65359477124183, 61728395, 5847953216374269, 5, 5291, 5, 48309178743961352657, 4625, 4, 42735, 4115226337448559670781893, 396825
OFFSET
1,2
LINKS
FORMULA
a(n) = A244859(n)/n.
EXAMPLE
For n = 7, 15873*7 = 111111 and this is the least positive multiple of 7 that is either a repunit or of the form 1111...000.
CROSSREFS
Cf. A244859, A079339, A004290. Equal to A079339 for the first 6 terms.
Sequence in context: A157809 A079339 A257343 * A043075 A096673 A144960
KEYWORD
nonn,base
AUTHOR
Chai Wah Wu, Jul 08 2014
STATUS
approved