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A248910 Numbers with no zeros in base-6 representation.

%I A248910 #23 Jun 29 2025 04:18:13
%S A248910 1,2,3,4,5,7,8,9,10,11,13,14,15,16,17,19,20,21,22,23,25,26,27,28,29,
%T A248910 31,32,33,34,35,43,44,45,46,47,49,50,51,52,53,55,56,57,58,59,61,62,63,
%U A248910 64,65,67,68,69,70,71,79,80,81,82,83,85,86,87,88,89,91,92
%N A248910 Numbers with no zeros in base-6 representation.
%C A248910 Different from A039215, A047253, A184522, A187390, A194386.
%H A248910 Reinhard Zumkeller, <a href="/A248910/b248910.txt">Table of n, a(n) for n = 1..10000</a>
%H A248910 Wikipedia, <a href="http://www.wikipedia.org/wiki/Senary">Senary</a>
%H A248910 <a href="/index/Ar#6-automatic">Index entries for 6-automatic sequences</a>.
%t A248910 Select[Range[100], DigitCount[#,6, 0] == 0 &] (* _Paolo Xausa_, Jun 29 2025 *)
%o A248910 (Haskell)
%o A248910 a248910 n = a248910_list !! (n-1)
%o A248910 a248910_list = iterate f 1 where
%o A248910    f x = 1 + if r < 5 then x else 6 * f x'  where (x', r) = divMod x 6
%o A248910 (PARI) isok(m) = vecmin(digits(m, 6)) > 0; \\ _Michel Marcus_, Jan 23 2022
%o A248910 (Python)
%o A248910 from sympy import integer_log
%o A248910 def A248910(n):
%o A248910     m = integer_log(k:=(n<<2)+1,5)[0]
%o A248910     return sum((1+(k-5**m)//(5**j<<2)%5)*6**j for j in range(m)) # _Chai Wah Wu_, Jun 28 2025
%Y A248910 Cf. A007092, A100969 (subsequence).
%Y A248910 Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A255805 (base 8), A255808 (base 9), A052382 (base 10).
%K A248910 nonn,base,easy
%O A248910 1,2
%A A248910 _Reinhard Zumkeller_, Mar 08 2015