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Numbers with no zeros in base-9 representation.
7

%I #14 Jun 29 2019 03:57:40

%S 1,2,3,4,5,6,7,8,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,28,

%T 29,30,31,32,33,34,35,37,38,39,40,41,42,43,44,46,47,48,49,50,51,52,53,

%U 55,56,57,58,59,60,61,62,64,65,66,67,68,69,70,71,73,74,75

%N Numbers with no zeros in base-9 representation.

%C a(n) = A168183(n) for n <= 72.

%H Reinhard Zumkeller, <a href="/A255808/b255808.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Ar#3-automatic">Index entries for 3-automatic sequences</a>.

%t Select[Range[100],DigitCount[#,9,0]==0&] (* or *) With[{upto=100}, Complement[ Range[upto],9*Range[Floor[upto/9]]]] (* _Harvey P. Dale_, May 29 2019 *)

%o (Haskell)

%o a255808 n = a255808_list !! (n-1)

%o a255808_list = iterate f 1 where

%o f x = 1 + if r < 8 then x else 9 * f x' where (x', r) = divMod x 9

%o (PARI) isok(n) = vecmin(digits(n, 9)) != 0; \\ _Michel Marcus_, Jun 29 2019

%Y Cf. A007095, A100973 (subsequence).

%Y Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A248910 (base 6), A255805 (base 8), A052382 (base 10).

%K nonn,base,easy

%O 1,2

%A _Reinhard Zumkeller_, Mar 08 2015