A045042 Numbers whose base-4 representation contains exactly one 0 and no 2's.

0, 4, 12, 17, 19, 20, 28, 49, 51, 52, 60, 69, 71, 77, 79, 81, 83, 84, 92, 113, 115, 116, 124, 197, 199, 205, 207, 209, 211, 212, 220, 241, 243, 244, 252, 277, 279, 285, 287, 309, 311, 317, 319, 325, 327, 333, 335, 337, 339, 340, 348

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= proc(n) local L;
  L:= convert(n, base, 4);
  not member(2, L) and numboccur(0, L)=1
end proc:
select(filter, [$0..1000]); # Robert Israel, Nov 22 2024

Mathematica

Select[Range[0, 400], DigitCount[#, 4, 0]==1&&DigitCount[#, 4, 2]==0&] (* Harvey P. Dale, Oct 22 2015 *)

Crossrefs

Cf. A007090.

Sequence in context: A048661 A036047 A356812 * A367930 A095099 A134860

Adjacent sequences: A045039 A045040 A045041 * A045043 A045044 A045045

Keyword

nonn,base

Author

Clark Kimberling

Extensions

a(1) = 0 inserted by Georg Fischer, Jun 28 2019

Status

approved