A039473 - OEIS

%I #26 Jun 30 2021 04:32:02

%S 50,70,171,191,292,312,413,433,490,501,512,523,545,550,551,552,553,

%T 555,557,558,559,560,567,578,589,600,655,675,730,741,752,763,770,771,

%U 772,773,775,777,778,779,780,785,807,818,829,840,897,917,1018,1038

%N Numbers whose base-11 representation has the same nonzero number of 4's and 6's.

%t okQ[n_]:=Module[{dc4=DigitCount[n,11,4]},dc4>0&&dc4==DigitCount[n,11,6]]

%t Select[Range[1100],okQ]  (* _Harvey P. Dale_, Jan 09 2011 *)

%K nonn,base,easy

%O 1,1

%A _Olivier Gérard_