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Lexicographically earliest sequence of distinct positive integers such that a(n) and a(n-1) share at least one identical trit at the same position in their balanced ternary representations.
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%I #8 Mar 24 2023 18:00:50

%S 1,4,2,3,6,5,7,8,9,10,11,12,13,16,14,15,17,18,19,20,21,22,23,24,25,26,

%T 27,28,29,30,31,32,33,34,35,36,37,38,39,40,43,41,42,44,45,46,47,48,49,

%U 50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67

%N Lexicographically earliest sequence of distinct positive integers such that a(n) and a(n-1) share at least one identical trit at the same position in their balanced ternary representations.

%C Conjecture: Suppose n is the x-th fixed point such that n-1 is not a fixed point. Then for all k such that n < k < (3^(x + 2) + 1)/2, k is also a fixed point.

%e Table of initial terms (T is a digit of the value -1):

%e n | a(n) | BAL

%e ---+------+-------

%e 1 | 1 | 1

%e 2 | 4 | 11

%e 3 | 2 | 1T

%e 4 | 3 | 10

%e 5 | 6 | 1T0

%e 6 | 5 | 1TT

%e 7 | 7 | 1T1

%e 8 | 8 | 10T

%e 9 | 9 | 100

%e 10 | 10 | 101

%e 11 | 11 | 11T

%e 12 | 12 | 110

%e 13 | 13 | 111

%e 14 | 16 | 1TT1

%e 15 | 14 | 1TTT

%e 16 | 15 | 1TT0

%e 17 | 17 | 1T0T

%e 18 | 18 | 1T00

%e 19 | 19 | 1T01

%e 20 | 20 | 1T1T

%K base,nonn

%O 1,2

%A _Jodi Spitz_, Mar 22 2023