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A039145 Numbers whose base-10 representation has the same number of 4's and 9's. 1

%I

%S 0,1,2,3,5,6,7,8,10,11,12,13,15,16,17,18,20,21,22,23,25,26,27,28,30,

%T 31,32,33,35,36,37,38,49,50,51,52,53,55,56,57,58,60,61,62,63,65,66,67,

%U 68,70,71,72,73,75,76,77,78,80,81,82,83,85,86,87,88,94,100,101,102

%N Numbers whose base-10 representation has the same number of 4's and 9's.

%t Select[Range[0, 200], DigitCount[#, 10, 4] == DigitCount[#, 10, 9] &] (* _Vincenzo Librandi_, Oct 27 2016 *)

%o (MAGMA) [n: n in [0..120] | Multiplicity(S, 4) eq Multiplicity(S, 9) where S is {*d: d in Intseq(n)*}]; // _Vincenzo Librandi_, Oct 27 2016

%K nonn,base,easy

%O 1,3

%A _Olivier GĂ©rard_

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Last modified May 18 06:28 EDT 2022. Contains 353783 sequences. (Running on oeis4.)