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Lexicographically earliest sequence of distinct positive terms such that a(1) = 2 and for any n > 0, the binary representation of Sum_{k=1..n} a(k) starts with the binary representation of a(n).
2

%I #11 Jul 20 2018 11:55:05

%S 2,1,3,5,10,6,8,4,12,7,19,11,29,16,18,21,24,13,69,39,45,51,27,14,30,

%T 15,33,17,36,9,84,96,110,28,60,31,32,68,35,75,80,20,42,43,22,94,48,50,

%U 25,52,26,55,57,58,125,64,66,142,73,37,77,79,40,41,175,44

%N Lexicographically earliest sequence of distinct positive terms such that a(1) = 2 and for any n > 0, the binary representation of Sum_{k=1..n} a(k) starts with the binary representation of a(n).

%C This sequence is a binary variant of A316918.

%C This sequence is conjectured to be infinite.

%C This sequence is conjectured to be a permutation of the natural numbers.

%H Rémy Sigrist, <a href="/A316993/b316993.txt">Table of n, a(n) for n = 1..10000</a>

%H Rémy Sigrist, <a href="/A316993/a316993.png">Colored scatterplot of the first 200000 terms</a> (where the color is function of A070939(Sum_{k=1..n} a(k)) - A070939(a(n)))

%H Rémy Sigrist, <a href="/A316993/a316993_1.png">Scatterplot of the ordinal transform of the first 25000 terms of A070939(Sum_{k=1..n} a(k)) - A070939(a(n))</a>

%H Rémy Sigrist, <a href="/A316993/a316993.txt">C++ program for A316993</a>

%e The first terms, alongside the binary representations of a(n) and of Sum_{k=1..n} a(k), are:

%e n a(n) bin(a(n)) bin(Sum_{k=1..n} a(k))

%e -- ---- --------- ----------------------

%e 1 2 10 10

%e 2 1 1 11

%e 3 3 11 110

%e 4 5 101 1011

%e 5 10 1010 10101

%e 6 6 110 11011

%e 7 8 1000 100011

%e 8 4 100 100111

%e 9 12 1100 110011

%e 10 7 111 111010

%e 11 19 10011 1001101

%e 12 11 1011 1011000

%e 13 29 11101 1110101

%e 14 16 10000 10000101

%e 15 18 10010 10010111

%e 16 21 10101 10101100

%e 17 24 11000 11000100

%e 18 13 1101 11010001

%e 19 69 1000101 100010110

%e 20 39 100111 100111101

%o (C++) See Links section.

%Y Cf. A070939, A316918.

%K nonn,base

%O 1,1

%A _Rémy Sigrist_, Jul 18 2018