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Limit of the recursion B_[k] = P[k](B_[k-1]), where B_[0] = (1,2,3,4,5,...) and P[k] is the permutation that permutes the entries k+j and 2k + j for all j = 1,..,k.
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%I #13 Jul 17 2023 08:57:40

%S 1,3,5,7,4,6,12,14,16,11,2,21,23,25,10,17,30,32,34,22,8,39,41,43,27,

%T 28,48,50,52,20,33,57,59,61,38,9,66,68,70,26,44,75,77,79,49,18,84,86,

%U 88,54,55,93,95,97,36,60,102,104,106,65,40,111,113,115,42,71,120,122,124

%N Limit of the recursion B_[k] = P[k](B_[k-1]), where B_[0] = (1,2,3,4,5,...) and P[k] is the permutation that permutes the entries k+j and 2k + j for all j = 1,..,k.

%C Conjectured to be a permutation of the natural numbers.

%H Sean A. Irvine, <a href="/A064537/b064537.txt">Table of n, a(n) for n = 1..10000</a>

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

%p k := 200: a := [seq(j,j=1..3*k)]: for i from 1 to k do; a := [seq(a[j],j=1..i),seq(a[j],j=2*i+1..3*i),seq(a[j],j=i+1..2*i),seq(a[j],j=3*i+1..3*k)]; od: seq(a[j],j=1..i);

%t k = 69; a = Range[1, 3k]; For[i = 1, i <= k, i++, a = Join[a[[1 ;; i]], a[[2i+1 ;; 3i]], a[[i+1 ;; 2i]], a[[3i+1 ;; 3k]]]]; a[[1 ;; k]] (* _Jean-François Alcover_, Oct 11 2012, after Maple *)

%Y "Inverse": A064791.

%K easy,nonn

%O 1,2

%A Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Oct 08 2001