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A055143 The first n digits of the juxtaposition of the base-2 numbers converted to decimal.

%I A055143 #17 Feb 16 2024 01:24:13
%S A055143 1,3,6,13,27,55,110,220,441,882,1765,3531,7063,14126,28253,56507,
%T A055143 113015,226031,452062,904124,1808248,3616497,7232994,14465988,
%U A055143 28931977,57863955,115727910,231455821,462911642,925823285,1851646570,3703293141,7406586283,14813172567
%N A055143 The first n digits of the juxtaposition of the base-2 numbers converted to decimal.
%H A055143 Michael S. Branicky, <a href="/A055143/b055143.txt">Table of n, a(n) for n = 1..3322</a>
%e A055143 1 (1); 11 (3); 110 (6); 1101 (13); 11011 (27); 110111 (55); ...
%t A055143 With[{c=Flatten[Table[IntegerDigits[n,2],{n,20}]]},Table[FromDigits[ Take[ c,k],2],{k,Length[c]}]] (* _Harvey P. Dale_, May 15 2021 *)
%o A055143 (Python)
%o A055143 from itertools import count, islice
%o A055143 def agen():
%o A055143     k, chap = 1, "1"
%o A055143     for n in count(1):
%o A055143         while len(chap) < n: k += 1; chap += bin(k)[2:]
%o A055143         yield int(chap[:n], 2)
%o A055143 print(list(islice(agen(), 34))) # _Michael S. Branicky_, Oct 06 2022
%Y A055143 Cf. A030190, A054633, A055074, A055144-A055150.
%K A055143 nonn,base
%O A055143 1,2
%A A055143 _Patrick De Geest_, Apr 15 2000
%E A055143 a(32) and beyond from _Michael S. Branicky_, Oct 06 2022