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A318839 Restricted growth sequence transform of A318838.

%I A318839 #6 Sep 05 2018 17:17:29
%S A318839 1,1,2,2,3,2,4,5,6,3,7,8,9,4,10,11,12,6,13,10,14,7,15,16,17,9,18,14,
%T A318839 19,10,20,21,22,12,23,24,25,13,26,27,28,14,29,22,30,15,31,32,33,17,34,
%U A318839 26,35,18,36,37,38,19,39,40,41,20,42,43,44,22,45,34,46,23,47,48,49,25,50,38,51,26,52,53,54,28,55,56,57,29,58,59,60,30,61,46,62,31,63
%N A318839 Restricted growth sequence transform of A318838.
%C A318839 For all i, j: a(i) = a(j) => A000010(i) = A000010(j).
%H A318839 Antti Karttunen, <a href="/A318839/b318839.txt">Table of n, a(n) for n = 1..65537</a>
%o A318839 (PARI)
%o A318839 up_to = 65537;
%o A318839 rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };
%o A318839 A007431(n) = sumdiv(n,d,moebius(n/d)*eulerphi(d));
%o A318839 A318838(n) = { my(m=1); fordiv(n,d,if((A007431(d)!=0),m *= prime(A007431(d)))); (m); };
%o A318839 v318839 = rgs_transform(vector(up_to,n,A318838(n)));
%o A318839 A318839(n) = v318839[n];
%Y A318839 Cf. A000010, A007431, A318838.
%Y A318839 Cf. also A318837.
%K A318839 nonn
%O A318839 1,3
%A A318839 _Antti Karttunen_, Sep 05 2018