%I #19 Sep 20 2015 20:33:55
%S 1,2,3,4,5,6,8,7,12,9,10,11,13,20,16,14,24,17,15,28,25,18,19,26,21,22,
%T 27,23,29,52,40,32,30,56,48,33,31,60,57,50,36,34,35,49,68,37,41,38,51,
%U 39,58,53,42,43,44,96,64,45,54,88,97,66,46,59,55,47,61
%N a(1) = 1; for n > 1, let s denote the binary representation of a(n-1) with the first bit omitted. Then a(n) is the smallest number not yet present whose binary representation starts with s, omitting leading zeros.
%C It seems clear that every number will appear. It would be nice to have a formal proof. - _N. J. A. Sloane_, Sep 20 2015
%H Alois P. Heinz, <a href="/A262374/b262374.txt">Table of n, a(n) for n = 1..20000</a>
%e : 1 ... 1
%e : 10 ... 2
%e : 11 ... 3
%e : 100 ... 4
%e : 101 ... 5
%e : 110 ... 6
%e : 1000 ... 8
%e : 111 ... 7
%e : 1100 ... 12
%e : 1001 ... 9
%e : 1010 ... 10
%e : 1011 ... 11
%e : 1101 ... 13
%e : 10100 ... 20
%e : 10000 ... 16
%e : 1110 ... 14
%e : 11000 ... 24
%e : 10001 ... 17
%Y Binary counterpart of A262356.
%Y A262381 gives the binary representations.
%Y Cf. A262388.
%K nonn,base
%O 1,2
%A _Allan C. Wechsler_, Sep 20 2015