A244960 Smallest positive multiple of n whose base 9 representation contains only 0's and 1's.

1, 10, 9, 820, 10, 90, 91, 5380840, 9, 10, 7381, 7380, 91, 66430, 90, 43644592, 6562, 90, 7372, 820, 819, 65692, 7291, 48427560, 7300, 66430, 81, 532252, 59131, 90, 66340, 48368512, 66429, 6562, 66430, 7380, 532171, 7372, 819, 5380840, 82, 597870, 66349

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Ed Pegg Jr., 'Binary' Puzzle

Eric M. Schmidt, Sage code to compute this sequence (use b=9)

Chai Wah Wu, Pigeonholes and repunits, Amer. Math. Monthly, 121 (2014), 529-533.

Mathematica

Module[{nn=15, b9}, b9=Rest[FromDigits[#, 9]&/@Tuples[{0, 1}, nn]]; Table[SelectFirst[ b9, Mod[#, n]==0&], {n, 100}]] (* Harvey P. Dale, Feb 03 2024 *)

Prog

(PARI) a(n, b=9) = if (n, k=1; while(vecmax(digits(k*n, b))>1, k++); k*n); \\ Michel Marcus, Jul 10 2014

Crossrefs

Cf. A004289 (written in base 9), A004290, A244954-A244959.

Sequence in context: A243035 A070252 A038311 * A282560 A335556 A286775

Adjacent sequences: A244957 A244958 A244959 * A244961 A244962 A244963

Keyword

nonn,base

Author

Eric M. Schmidt, Jul 09 2014

Extensions

Data corrected, offset corrected, and b-file replaced by Harvey P. Dale, Feb 03 2024

Status

approved