A285916 - OEIS

%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