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A308073 Lexicographically earliest sequence of positive terms such that for any distinct m and n, a(m) + dup(a(m+1)) <> a(n) + dup(a(n+1)) (where dup corresponds to A020330).

%I A308073 #9 May 11 2019 11:01:58
%S A308073 1,1,2,1,3,1,4,1,5,1,6,1,7,1,8,2,2,3,2,4,2,5,2,6,3,4,3,5,3,6,4,4,5,4,
%T A308073 6,5,5,6,6,7,3,7,4,7,5,7,6,8,3,8,4,8,5,8,6,9,3,9,4,9,5,9,6,10,3,10,7,
%U A308073 7,8,7,9,7,10,8,8,9,8,10,9,9,10,10,11,3
%N A308073 Lexicographically earliest sequence of positive terms such that for any distinct m and n, a(m) + dup(a(m+1)) <> a(n) + dup(a(n+1)) (where dup corresponds to A020330).
%H A308073 Rémy Sigrist, <a href="/A308073/b308073.txt">Table of n, a(n) for n = 1..10000</a>
%e A308073 The first terms, alongside a(n) + dup(a(n+1)), are:
%e A308073   n   a(n)  a(n)+dup(a(n+1))
%e A308073   --  ----  ----------------
%e A308073    1     1                 4
%e A308073    2     1                11
%e A308073    3     2                 5
%e A308073    4     1                16
%e A308073    5     3                 6
%e A308073    6     1                37
%e A308073    7     4                 7
%e A308073    8     1                46
%e A308073    9     5                 8
%e A308073   10     1                55
%o A308073 (PARI) s=0; v=1; for(n=1, 84, print1(v", "); for (w=1, oo, if (!bittest(s,x=v+w*(1+2^#binary(w))), s+=2^x; v=w; break)))
%Y A308073 See A308057 for other variants.
%Y A308073 Cf. A020330.
%K A308073 nonn,look,base
%O A308073 1,3
%A A308073 _Rémy Sigrist_, May 11 2019