A270040 - OEIS

%I #13 Mar 10 2016 20:55:15

%S 10,11,12,13,15,15,17,17,66,75,75,86,86,90,138,138,138,138,138,138,

%T 138,138,138,182,182,182,182,182,182,182,182,182,185,781817578165,

%U 781817578165,7826560751018861596150680

%N a(n) = Smallest m >= 9 containing no fours when represented in any base from 5 through n.

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

%C These numbers are not very Foury, at least not initially. (See A268236.)

%H Nathan Fox, <a href="/A270040/b270040.txt">Table of n, a(n) for n = 5..59</a>

%t Table[SelectFirst[Range[9, 10^3], Total@ Map[Function[k, DigitCount[#, k, 4]], Range[5, n]] == 0 &], {n, 5, 60}] /. n_ /; MissingQ@ n -> Nothing (* _Michael De Vlieger_, Mar 10 2016, Version 10.2 *)

%Y Cf. A268236, A268237, A270030, A270037, A270038, A216192, A270039, A270041, A270042, A270043, A270044, A270045.

%K nonn,base

%O 5,1

%A _Nathan Fox_, Mar 09 2016