cp's OEIS Frontend

A381259 Numbers obtained by concatenating powers of 2, sorted into increasing order.

%I A381259 #22 Feb 20 2025 12:58:18
%S A381259 1,2,4,8,11,12,14,16,18,21,22,24,28,32,41,42,44,48,64,81,82,84,88,111,
%T A381259 112,114,116,118,121,122,124,128,132,141,142,144,148,161,162,164,168,
%U A381259 181,182,184,188,211,212,214,216,218,221,222,224,228,232,241,242,244,248,256,264
%N A381259 Numbers obtained by concatenating powers of 2, sorted into increasing order.
%C A381259 Take the list {2^i: i >= 0} and concatenate its terms (allowing multiple copies) in any order; then sort the result into increasing order.
%C A381259 The term a(32) = 128 is a power of 2 as well as the concatenation of several powers of 2. - _Rémy Sigrist_, Feb 20 2025
%H A381259 Rémy Sigrist, <a href="/A381259/b381259.txt">Table of n, a(n) for n = 1..11921</a>
%H A381259 Rémy Sigrist, <a href="/A381259/a381259.gp.txt">PARI program</a>
%e A381259 11 is a term because it is the concatenation of 1 = 2^0 with itself;
%e A381259 12 is a term because it is the concatenation of 1 = 2^0 with 2 = 2^1;
%e A381259 32 is a term because it is equal to 2^5;
%e A381259 168 is a term because it is the concatenation of 16 = 2^4 with 8 = 2^3.
%e A381259 0 is not a term because it is not a power of 2.
%o A381259 (PARI) \\ See Links section.
%Y A381259 Supersequence of A028846.
%Y A381259 Some subsequences: A000079, A045507, A178664.
%Y A381259 Cf. A152242.
%K A381259 nonn,base,easy
%O A381259 1,2
%A A381259 _Stefano Spezia_, Feb 18 2025