%I #7 Oct 19 2021 21:44:35
%S 1,4,6,2,7,3,5,9,8,11,10,13,12,15,14,17,16,21,24,29,18,30,33,19,34,39,
%T 46,49,20,22,50,57,23,25,58,63,66,71,26,72,79,86,89,96,101,27,102,105,
%U 28,31,106,113,118,125,134,139,32,35,140,143,148,151,36,152,157,37,158
%N Self-inverse permutation of the natural numbers, induced by A137661.
%C a(a(n)) = n; A137661(a(n)) = A137661(n).
%H R. Zumkeller, <a href="/A137662/b137662.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%Y Cf. A137661.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Feb 04 2008