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a(n) is the greatest number k not yet in the sequence such that A022290(n) = A022290(k).
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%I #13 Mar 30 2023 16:43:34

%S 0,1,2,4,3,5,8,9,6,7,10,16,12,17,18,20,11,13,14,19,15,21,32,33,24,25,

%T 34,36,35,37,40,41,22,23,26,28,27,29,38,39,30,31,42,64,48,65,66,68,44,

%U 49,50,67,52,69,72,73,70,71,74,80,76,81,82,84,43,45,46,51

%N a(n) is the greatest number k not yet in the sequence such that A022290(n) = A022290(k).

%C This sequence is a self-inverse permutation of the nonnegative integers.

%H Rémy Sigrist, <a href="/A360434/b360434.txt">Table of n, a(n) for n = 0..10922</a>

%H Rémy Sigrist, <a href="/A360434/a360434.gp.txt">PARI program</a>

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

%F a(A345101(n, k)) = A345101(n, A000119(n) + 1 - k).

%F a(A003754(n+1)) = A003714(n).

%F a(A003714(n)) = A003754(n+1).

%e There are three numbers k such that A022290(k) = 11: 15, 19, 20,

%e - so a(15) = 20,

%e a(19) = 19,

%e a(20) = 15.

%o (PARI) See Links section.

%Y See A360415 for a similar sequence.

%Y Cf. A000119, A003714, A003754, A022290, A345101.

%K nonn,base

%O 0,3

%A _Rémy Sigrist_, Feb 07 2023