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Self-inverse permutation: in base 3, reverse the lengths of runs of consecutive equal digits.
1

%I #7 Apr 30 2017 11:49:50

%S 0,1,2,3,4,5,6,7,8,12,10,11,9,13,17,15,16,14,24,19,20,21,25,23,18,22,

%T 26,39,28,29,30,37,32,33,34,38,36,31,35,27,40,53,45,49,44,42,46,47,48,

%U 43,50,51,52,41,78,55,56,57,73,59,60,61,74,75,64,65,66,79

%N Self-inverse permutation: in base 3, reverse the lengths of runs of consecutive equal digits.

%C This sequence can be seen as an analog of A056539 for the base 3.

%C For any n>=0, n and a(n) have the same number of digits in base 3.

%H Rémy Sigrist, <a href="/A285916/b285916.txt">Table of n, a(n) for n = 0..6560</a>

%H Rémy Sigrist, <a href="/A285916/a285916.gp.txt">PARI program for A285916</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%e The first terms for which n<>a(n) are:

%e Decimal: Base 3:

%e n a(n) n a(n)

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

%e 9 12 100 110

%e 12 9 110 100

%e 14 17 112 122

%e 17 14 122 112

%e 18 24 200 220

%e 22 25 211 221

%e 24 18 220 200

%e 25 22 221 211

%e 27 39 1000 1110

%e 31 37 1011 1101

%e 35 38 1022 1102

%e 37 31 1101 1011

%e 38 35 1102 1022

%e 39 27 1110 1000

%e 41 53 1112 1222

%e 42 45 1120 1200

%Y Cf. A056539.

%K nonn,base,look

%O 0,3

%A _Rémy Sigrist_, Apr 28 2017