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a(n) = index of n in A353709, or -1 if n does not appear there.
6

%I #8 May 09 2022 23:09:07

%S 0,1,2,5,3,13,10,53,4,22,14,56,7,34,17,76,6,9,20,69,24,38,42,86,28,31,

%T 49,90,46,185,73,245,8,19,23,26,30,50,94,322,11,102,39,105,70,109,252,

%U 549,15,65,98,117,80,83,124,1047,113,225,242,692,249,1209,553,1647,12,16,29,114,21,137,63,329,25,99,133,312,60,140,339,1007,54,175,148,189,57,238

%N a(n) = index of n in A353709, or -1 if n does not appear there.

%C If, as conjectured, A353709 is a permutation of the nonnegative integers, then this is the inverse permutation.

%H Rémy Sigrist, <a href="/A353717/b353717.txt">Table of n, a(n) for n = 0..16383</a>

%H Rémy Sigrist, <a href="/A353717/a353717.txt">C++ program</a>

%p b:= proc() false end: t:= 2:

%p g:= proc(n) option remember; global t; local k; if n<2 then n

%p else for k from t while b(k) or Bits[And](k, g(n-2))>0

%p or Bits[And](k, g(n-1))>0 do od; b(k):=true;

%p while b(t) do t:=t+1 od; k fi

%p end:

%p a:= proc() local t, a; t, a:= -1, proc() -1 end;

%p proc(n) local h;

%p while a(n) = -1 do

%p t:= t+1; h:= g(t);

%p if a(h) = -1 then a(h):= t fi

%p od; a(n)

%p end

%p end():

%p seq(a(n), n=0..85); # _Alois P. Heinz_, May 09 2022

%o (C++) See Links section.

%Y Cf. A353709.

%K nonn

%O 0,3

%A _N. J. A. Sloane_, May 09 2022