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A244958
Smallest positive multiple of n whose base-7 representation contains only 0's and 1's.
2
1, 8, 57, 8, 50, 19608, 7, 8, 351, 50, 2409, 19608, 351, 56, 2745, 400, 16864, 134856, 57, 400, 399, 2794, 17158, 19608, 50, 19552, 351, 56, 137257, 120450, 16864, 2752, 2409, 16864, 350, 134856, 117993, 19608, 351, 400, 134849, 137256, 344, 16808, 2745
OFFSET
1,2
LINKS
Ed Pegg Jr., 'Binary' Puzzle
Eric M. Schmidt, Sage code to compute this sequence (use b=7)
Chai Wah Wu, Pigeonholes and repunits, Amer. Math. Monthly, 121 (2014), 529-533.
MATHEMATICA
With[{cl=Rest[{FromDigits[#, 7], FromDigits[#]}&/@Tuples[{0, 1}, 7]]}, Table[SelectFirst[cl, Mod[ #[[1]], n]==0&], {n, 50}]][[;; , 1]] (* Harvey P. Dale, Feb 01 2024 *)
CROSSREFS
Cf. A004287 (written in base 7), A004290, A244954-A244960.
Sequence in context: A009089 A296466 A202863 * A043071 A304352 A305915
KEYWORD
nonn,base
AUTHOR
Eric M. Schmidt, Jul 09 2014
EXTENSIONS
Data corrected, Offset corrected, Mathematica program corrected and replaced, and b-file replaced by Harvey P. Dale, Feb 01 2024
STATUS
approved