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A033033 Numbers all of whose base 7 digits are odd. 4

%I #16 Sep 08 2022 08:44:51

%S 1,3,5,8,10,12,22,24,26,36,38,40,57,59,61,71,73,75,85,87,89,155,157,

%T 159,169,171,173,183,185,187,253,255,257,267,269,271,281,283,285,400,

%U 402,404,414,416,418,428,430,432,498,500,502,512

%N Numbers all of whose base 7 digits are odd.

%H David A. Corneth, <a href="/A033033/b033033.txt">Table of n, a(n) for n = 1..10000</a>

%e 38 in base 7 is 53_7. All the digits of 38 in base 7; 5 and 3; are odd. So 38 is in the sequence. - _David A. Corneth_, Aug 24 2019

%t Select[Range[600],AllTrue[IntegerDigits[#,7],OddQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Sep 28 2014 *)

%o (PARI) is(n) = {my(d = Set(digits(n, 7))); for(i = 1, #d, if(d[i]%2 == 0, return(0))); 1} \\ _David A. Corneth_, Aug 24 2019

%o (Magma) [m:m in [1..600]| Intseq(m,7) subset {1,3,5}]; // _Marius A. Burtea_, Aug 24 2019

%Y Cf. A007093, A014261.

%K nonn,easy,base

%O 1,2

%A _Clark Kimberling_

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Last modified April 19 11:31 EDT 2024. Contains 371792 sequences. (Running on oeis4.)