

A216192


a(n) = Smallest m >= 5 containing no twos when represented in any base from 3 through n.


12




OFFSET

3,1


COMMENTS

If a(11) exists, it contains over 3000 digits.
No more terms < 10^154400. Most likely there are no more terms.  Chai Wah Wu, Mar 17 2016


LINKS



EXAMPLE

In base 3, 5=12, 6=20, 7=21, 8=22, 9=100. The first representation containing no twos is that of 9, so a(3)=9.


MATHEMATICA

Table[SelectFirst[Range[5, 10^3], Total@ Map[Function[k, DigitCount[#, k, 2]], Range[3, n]] == 0 &], {n, 3, 20}] /. n_ /; MissingQ@ n > Nothing (* Michael De Vlieger, Mar 09 2016, Version 10.2 *)


CROSSREFS



KEYWORD

nonn,hard,more,base


AUTHOR



STATUS

approved



