Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #19 Nov 22 2024 19:43:55
%S 0,4,12,17,19,20,28,49,51,52,60,69,71,77,79,81,83,84,92,113,115,116,
%T 124,197,199,205,207,209,211,212,220,241,243,244,252,277,279,285,287,
%U 309,311,317,319,325,327,333,335,337,339,340,348
%N Numbers whose base-4 representation contains exactly one 0 and no 2's.
%H Robert Israel, <a href="/A045042/b045042.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local L;
%p L:= convert(n,base,4);
%p not member(2,L) and numboccur(0,L)=1
%p end proc:
%p select(filter, [$0..1000]); # _Robert Israel_, Nov 22 2024
%t Select[Range[0,400],DigitCount[#,4,0]==1&&DigitCount[#,4,2]==0&] (* _Harvey P. Dale_, Oct 22 2015 *)
%Y Cf. A007090.
%K nonn,base
%O 1,2
%A _Clark Kimberling_
%E a(1) = 0 inserted by _Georg Fischer_, Jun 28 2019