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%I #16 Jun 01 2024 11:30:17
%S 27,83,87,99,135,163,165,171,189,251,263,267,299,303,315,407,411,423,
%T 459,491,493,497,501,505,507,515,519,531,541,543,549,569,573,585,621,
%U 649,651,657,675,755,791,803,807,899,911,915
%N Numbers whose base-3 representation contains exactly three 0's and one 1.
%t Select[Range[1000],DigitCount[#,3,0]==3&&DigitCount[#,3,1]==1&] (* _Harvey P. Dale_, May 10 2024 *)
%o (PARI) upto(N)=my(d); [n |n<-[0..N], #(d=vecsort(digits(n, 3)))>=4 && d[1..4]==[0,0,0,1] && (4==#d || 2==d[5])]; \\ _Ruud H.G. van Tol_, Jun 01 2024
%Y Cf. A007089.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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