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A031944 Numbers in which digits 0,1,2 all occur in base 3.

%I A031944 #21 Feb 16 2025 08:32:36
%S A031944 11,15,19,21,29,32,33,34,35,38,42,45,46,47,48,51,55,57,58,59,61,63,64,
%T A031944 65,66,69,73,75,83,86,87,88,89,92,95,96,97,98,99,100,101,102,103,104,
%U A031944 105,106,107,110,113,114,115,116,119,123,126,127,128,129,132,135
%N A031944 Numbers in which digits 0,1,2 all occur in base 3.
%C A031944 A043530(a(n)) = 3; complement of A154314. - _Reinhard Zumkeller_, Jan 07 2009
%C A031944 A212193(a(n)) = 3. - _Reinhard Zumkeller_, May 04 2012
%H A031944 Reinhard Zumkeller, <a href="/A031944/b031944.txt">Table of n, a(n) for n = 1..10000</a>
%H A031944 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Ternary.html">Ternary</a>
%H A031944 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PandigitalNumber.html">Pandigital Number</a>
%H A031944 Wikipedia, <a href="http://en.wikipedia.org/wiki/Ternary_numeral_system">Ternary numeral system</a>
%H A031944 Wikipedia, <a href="http://en.wikipedia.org/wiki/Pandigital_number">Pandigital number</a>
%t A031944 Select[Range[200],Min[DigitCount[#,3]]>0&] (* _Harvey P. Dale_, Nov 21 2015 *)
%o A031944 (Haskell)
%o A031944 import Data.List (elemIndices)
%o A031944 a031944 n = a031944_list !! (n-1)
%o A031944 a031944_list = elemIndices 3 a212193_list
%o A031944 -- _Reinhard Zumkeller_, May 04 2012
%o A031944 (Python)
%o A031944 from sympy.ntheory import count_digits
%o A031944 def ok(n): c = count_digits(n, 3); return all(c[d] > 0 for d in [0, 1, 2])
%o A031944 print([k for k in range(136) if ok(k)]) # _Michael S. Branicky_, Nov 15 2021
%Y A031944 Cf. A043530, A049354, A154314, A212193.
%K A031944 nonn,base
%O A031944 1,1
%A A031944 _Clark Kimberling_