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A285916 Self-inverse permutation: in base 3, reverse the lengths of runs of consecutive equal digits.

%I A285916 #7 Apr 30 2017 11:49:50
%S A285916 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 A285916 26,39,28,29,30,37,32,33,34,38,36,31,35,27,40,53,45,49,44,42,46,47,48,
%U A285916 43,50,51,52,41,78,55,56,57,73,59,60,61,74,75,64,65,66,79
%N A285916 Self-inverse permutation: in base 3, reverse the lengths of runs of consecutive equal digits.
%C A285916 This sequence can be seen as an analog of A056539 for the base 3.
%C A285916 For any n>=0, n and a(n) have the same number of digits in base 3.
%H A285916 Rémy Sigrist, <a href="/A285916/b285916.txt">Table of n, a(n) for n = 0..6560</a>
%H A285916 Rémy Sigrist, <a href="/A285916/a285916.gp.txt">PARI program for A285916</a>
%H A285916 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%e A285916 The first terms for which n<>a(n) are:
%e A285916 Decimal:    Base 3:
%e A285916 n   a(n)    n       a(n)
%e A285916 -   ----    ---     ----
%e A285916 9   12      100     110
%e A285916 12  9       110     100
%e A285916 14  17      112     122
%e A285916 17  14      122     112
%e A285916 18  24      200     220
%e A285916 22  25      211     221
%e A285916 24  18      220     200
%e A285916 25  22      221     211
%e A285916 27  39      1000    1110
%e A285916 31  37      1011    1101
%e A285916 35  38      1022    1102
%e A285916 37  31      1101    1011
%e A285916 38  35      1102    1022
%e A285916 39  27      1110    1000
%e A285916 41  53      1112    1222
%e A285916 42  45      1120    1200
%Y A285916 Cf. A056539.
%K A285916 nonn,base,look
%O A285916 0,3
%A A285916 _Rémy Sigrist_, Apr 28 2017