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Consider the binary Champernowne sequence (A030190): smallest number m such that in binary representation n is contained in the concatenation of m and its successors.
4

%I #11 Jun 24 2021 13:42:59

%S 0,1,2,1,4,2,1,3,8,4,10,2,3,1,3,7,16,8,4,9,18,10,21,2,7,3,9,1,3,5,7,

%T 15,32,16,8,17,36,4,9,19,34,18,10,10,37,21,2,6,15,7,3,12,19,9,21,1,7,

%U 3,19,5,7,13,15,31,64,32,16,33,8,34,17,35,68,36,18,4,73,9,19,39,66,34,20,18

%N Consider the binary Champernowne sequence (A030190): smallest number m such that in binary representation n is contained in the concatenation of m and its successors.

%C a(n)<=n; see A083655 for numbers m with a(m)=m;

%C a(A055143(n))=1;

%C A083654(n)-1 = number of successors of a(n) to cover n.

%H Rémy Sigrist, <a href="/A083653/b083653.txt">Table of n, a(n) for n = 0..8191</a>

%H Rémy Sigrist, <a href="/A083653/a083653.gp.txt">PARI program for A083653</a>

%e n=24: '11000'=24 is a suffix of the concatenation of the first 8 numbers: '0'1'10'11'100'101'110'111'1000', therefore a(24)=7 and A083654(24)=2.

%o (PARI) See Links section.

%Y Cf. A030190, A030304, A007088, A345672 (decimal analog).

%Y Cf. A055143, A083654, A083655.

%K nonn,base

%O 0,3

%A _Reinhard Zumkeller_, May 01 2003

%E Edited by _Charles R Greathouse IV_, Apr 26 2010