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a(n) = Smallest m >= 3 containing no ones when represented in any base from 3 through n.
9

%I #15 Oct 14 2019 04:44:36

%S 6,8,60,560,870899850,871017138,871017138,65473886952,65473886954

%N a(n) = Smallest m >= 3 containing no ones when represented in any base from 3 through n.

%C It remains to be determined if the sequence is finite.

%C a(12) > 3.4*10^30, if it exists. - _Giovanni Resta_, Oct 14 2019

%t Table[SelectFirst[Range[3, 10^3], Total@ Map[Function[k, DigitCount[#, k, 1]], Range[3, n]] == 0 &], {n, 3, 7}] /. n_ /; MissingQ@ n -> Nothing (* _Michael De Vlieger_, Mar 10 2016, Version 10.2 *)

%Y Cf. A270028, A270037, A216192, A270039, A270040, A270041, A270042, A270043, A270044, A270045.

%K nonn,base,more

%O 3,1

%A _Nathan Fox_, Mar 09 2016