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%I #12 May 27 2023 20:37:35
%S 63,127,191,223,239,247,251,253,254,383,447,479,495,503,507,509,510,
%T 639,703,735,751,759,763,765,766,863,879,887,891,893,894,927,943,951,
%U 955,957,958,983,987,989,990,999,1003,1005,1006,1013
%N Numbers whose base-4 representation contains no 0's and exactly three 3's.
%H Vincenzo Librandi, <a href="/A045064/b045064.txt">Table of n, a(n) for n = 1..2500</a>
%t Select[Range[7000], DigitCount[#, 4, 0] == 0 && DigitCount[#, 4, 3] == 3 &] (* _Vincenzo Librandi_, Sep 21 2016 *)
%Y Different from A031468.
%Y Cf. A007090.
%K nonn,base
%O 1,1
%A _Clark Kimberling_