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When expressed in base 2 and then interpreted in base 4, is a multiple of the original number.
19

%I #19 Mar 03 2023 05:41:27

%S 0,1,2,4,7,8,14,16,21,28,31,32,42,56,62,64,73,84,112,124,127,128,146,

%T 168,219,224,248,254,256,273,292,336,341,438,448,496,508,511,512,546,

%U 584,672,682,876,896,992,1016,1022,1024,1057,1092,1168,1344,1364,1533

%N When expressed in base 2 and then interpreted in base 4, is a multiple of the original number.

%C From _Rémy Sigrist_, Mar 15 2017: (Start)

%C Also numbers n such that A000695(n) is a multiple of n.

%C If n belongs to this sequence, then 2*n also belongs to this sequence.

%C If 2*n belongs to this sequence, then n also belongs to this sequence.

%C (End)

%H Rémy Sigrist, <a href="/A062846/b062846.txt">Table of n, a(n) for n = 1..2001</a>

%e 7 in base 2 is 111, which interpreted in base 4 is 21=3*7

%t Join[{0},Select[Range[1600],Divisible[FromDigits[IntegerDigits[#,2],4],#]&]] (* _Harvey P. Dale_, Nov 29 2015 *)

%Y Cf. A000695.

%K base,nonn

%O 1,3

%A _Erich Friedman_, Jul 21 2001

%E Offset changed to 1 by _Georg Fischer_, Mar 03 2023