A045041 - OEIS

%I #12 May 28 2023 01:38:31

%S 170,426,618,666,678,681,683,686,698,746,938,1450,1642,1690,1702,1705,

%T 1707,1710,1722,1770,1962,2410,2458,2470,2473,2475,2478,2490,2538,

%U 2650,2662,2665,2667,2670,2682,2710,2713,2715,2718

%N Numbers whose base-4 representation contains no 0's and exactly four 2's.

%H Vincenzo Librandi, <a href="/A045041/b045041.txt">Table of n, a(n) for n = 1..4300</a>

%t Select[Range[20000], DigitCount[#, 4, 0] == 0 && DigitCount[#, 4, 2] == 4 &] (* _Vincenzo Librandi_, Sep 23 2016 *)

%Y Cf. A007090.

%K nonn,base

%O 1,1

%A _Clark Kimberling_