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%I #9 Mar 21 2023 15:03:51
%S 0,1,2,3,4,6,7,5,8,10,12,13,14,15,11,9,16,18,20,21,24,28,29,25,26,30,
%T 31,27,22,23,19,17,32,34,36,37,40,44,45,41,48,52,56,57,58,59,53,49,50,
%U 54,60,61,62,63,55,51,42,46,47,43,38,39,35,33,64,66,68,69
%N Inverse permutation to A361646.
%H Rémy Sigrist, <a href="/A361647/b361647.txt">Table of n, a(n) for n = 0..8192</a>
%H Rémy Sigrist, <a href="/A361647/a361647.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(n) < 2^k iff n < 2^k.
%e A361646(42) = 56, so a(56) = 42.
%o (PARI) See Links section.
%Y Cf. A361646.
%K nonn,base
%O 0,3
%A _Rémy Sigrist_, Mar 19 2023