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A244959 Smallest positive multiple of n whose base 8 representation contains only 0's and 1's.

%I A244959 #21 May 22 2025 10:21:39
%S A244959 1,8,9,8,65,72,299593,8,9,520,4169,72,65,2396744,585,64,4097,72,513,
%T A244959 520,17044041,33352,33281,72,266825,520,513,2396744,266249,4680,4681,
%U A244959 64,32769,32776,16814665,72,262145,4104,585,520,32841,136352328,36937,33352,585
%N A244959 Smallest positive multiple of n whose base 8 representation contains only 0's and 1's.
%H A244959 Harvey P. Dale, <a href="/A244959/b244959.txt">Table of n, a(n) for n = 1..1000</a>
%H A244959 Ed Pegg Jr., <a href="http://www.mathpuzzle.com/Binary.html">'Binary' Puzzle</a>
%H A244959 Eric M. Schmidt, <a href="/A004290/a004290_1.sage.txt">Sage code to compute this sequence</a> (use b=8)
%H A244959 Chai Wah Wu, <a href="http://www.jstor.org/stable/10.4169/amer.math.monthly.121.06.529">Pigeonholes and repunits</a>, Amer. Math. Monthly, 121 (2014), 529-533.
%t A244959 Module[{nn=10,b8},b8=Rest[FromDigits[#,8]&/@Tuples[{0,1},nn]];Table[SelectFirst[ b8,Mod[#,n]==0&],{n,100}]] (* _Harvey P. Dale_, Feb 03 2024 *)
%o A244959 (Python)
%o A244959 def A244959(n):
%o A244959     if n > 0:
%o A244959         for i in range(1,2**n):
%o A244959             x = int(bin(i)[2:],8)
%o A244959             if not x % n:
%o A244959                 return x
%o A244959     return 0 # _Chai Wah Wu_, Dec 30 2014
%Y A244959 Cf. A004288 (written in base 8), A004290, A244954-A244960.
%K A244959 nonn,base
%O A244959 1,2
%A A244959 _Eric M. Schmidt_, Jul 09 2014
%E A244959 Data corrected, offset corrected, and b-file replaced by _Harvey P. Dale_, Feb 03 2024