A045021 - OEIS

%I #12 May 28 2023 22:19:44

%S 69,81,84,278,279,281,285,293,309,326,327,329,333,338,339,344,348,353,

%T 356,369,372,389,401,404,453,465,468,533,581,593,596,789,837,849,852,

%U 1114,1115,1118,1119,1126,1127,1129,1133,1142

%N Numbers whose base-4 representation contains exactly one 0 and three 1's.

%H Vincenzo Librandi, <a href="/A045021/b045021.txt">Table of n, a(n) for n = 1..9000</a>

%t Select[Range[10000], DigitCount[#, 4, 0] == 1 && DigitCount[#, 4, 1] == 3 &] (* _Vincenzo Librandi_, Sep 21 2016 *)

%Y Cf. A007090.

%K nonn,base

%O 1,1

%A _Clark Kimberling_