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A169852 a(n) = position of n in A169851.

%I A169852 #11 Jan 02 2025 09:35:00
%S A169852 2,5,3,13,4,10,8,6,1,18,7,22,9,12,15,31,16,35,14,11,17,41,20,26,21,24,
%T A169852 28,56,25,60,29,19,30,27,33,66,34,23,38,73,37,80,39,43,40,88,44,49,45,
%U A169852 32,46,99,47,52,48,36,55,106,51,114,59,50,63,53,58,127,64,42,54,133,62,137,65
%N A169852 a(n) = position of n in A169851.
%C A169852 A generalization of A064421.
%H A169852 Robert Israel, <a href="/A169852/b169852.txt">Table of n, a(n) for n = 2..10000</a>
%p A169852 N:= 100: V:= Vector(N): count:= 1: x:= 10: V[10]:= 1: Cands:= [$2..9,$11..1000]: nC:= nops(Cands):
%p A169852 for iter from 2 while count < N-1 do
%p A169852   found:= false;
%p A169852   for i from 1 to nC do
%p A169852     if igcd(Cands[i],x) > 1 then
%p A169852       x:= Cands[i];
%p A169852       Cands:= subsop(i=NULL,Cands);
%p A169852       found:= true;
%p A169852       if x <= N then V[x]:= iter; count:= count+1;  fi;
%p A169852       break;
%p A169852      fi
%p A169852   od;
%p A169852   if not found then break fi
%p A169852 od:
%p A169852 convert(V[2..N],list); # _Robert Israel_, Dec 31 2024
%K A169852 nonn
%O A169852 2,1
%A A169852 _T. D. Noe_ and _N. J. A. Sloane_, Jun 02 2010