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%I #8 Mar 30 2012 18:50:44
%S 1,3,2,5,4,10,8,7,11,6,9,14,16,12,18,13,19,15,17,21,20,24,25,22,23,28,
%T 29,26,27,42,32,31,34,33,36,35,41,39,38,44,37,30,47,40,46,45,43,50,53,
%U 48,52,51,49,55,54,57,56,62,61,66,59,58,65,67,63,60,64,69,68,78,73,74
%N Smallest number <>n, not occurring earlier and having as many distinct prime factors as n has, with a(1) = 1.
%C Self-inverse integer permutation: a(a(n))=n.
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%o Contribution from _Franklin T. Adams-Watters_, Apr 16 2009: (Start)
%o (PARI) invect(v,n,x)=for(i=1,n,if(v[i]==x,return(1)));0
%o nextnew(v,n)=local(k);k=1;while(!R(n,k)||invect(v,n-1,k),k++);k
%o newvect(n)=local(v);v=vector(n);for(k=1,n,v[k]=nextnew(v,k));v
%o R(n,m)=omega(n)==omega(m)&&n!=m||n==1&&m==1
%o newvect(80) (End)
%Y Cf. A001221.
%Y Cf. A100527,A159587. [From _Franklin T. Adams-Watters_, Apr 16 2009]
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Jun 08 2004
%E Description corrected by _Franklin T. Adams-Watters_, Apr 07 2009
%E Values through a(72) verified by [From _Franklin T. Adams-Watters_, Apr 16 2009]
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