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A304085 Divisor-or-multiple permutation of natural numbers: a(n) = A052330(A304083(n)).

%I A304085 #6 May 12 2018 14:44:39
%S A304085 1,2,6,3,24,12,4,8,120,60,20,5,40,10,30,15,840,420,140,35,7,280,70,14,
%T A304085 210,105,21,168,84,28,56,7560,42,1890,945,315,63,9,3780,1260,252,36,
%U A304085 2520,630,126,18,1512,756,189,27,378,54,1080,540,180,45,360,90,270,135,83160,504,72,216,108,41580,13860,3465,693,99,11,27720,6930,1386,198,22,20790
%N A304085 Divisor-or-multiple permutation of natural numbers: a(n) = A052330(A304083(n)).
%C A304085 Each a(n) is always either a divisor or a multiple of a(n+1).
%H A304085 Antti Karttunen, <a href="/A304085/b304085.txt">Table of n, a(n) for n = 0..16383</a>
%H A304085 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A304085 a(n) = A052330(A304083(n)).
%o A304085 (PARI)
%o A304085 up_to_e = 16; \\ Good for computing up to n = (2^16)-1
%o A304085 v050376 = vector(up_to_e);
%o A304085 ispow2(n) = (n && !bitand(n,n-1));
%o A304085 i = 0; for(n=1,oo,if(ispow2(isprimepower(n)), i++; v050376[i] = n); if(i == up_to_e,break));
%o A304085 A050376(n) = v050376[n];
%o A304085 A052330(n) = { my(p=1,i=1); while(n>0, if(n%2, p *= A050376(i)); i++; n >>= 1); (p); };
%o A304085 A304085(n) = A052330(A304083(n)); \\ Needs also code from A304083
%Y A304085 Cf. A304086 (inverse).
%Y A304085 Cf. A304083, A304087.
%Y A304085 Cf. also A064736, A113552, A207901, A281978, A282291, A302350, A302781, A302783, A303751, A303771 for similar permutations.
%K A304085 nonn
%O A304085 0,2
%A A304085 _Antti Karttunen_, May 06 2018