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A319681 Restricted growth sequence transform of A319680.

%I A319681 #5 Sep 29 2018 18:42:16
%S A319681 1,2,3,4,5,6,6,7,8,9,9,10,11,12,13,14,15,16,17,18,19,20,20,21,22,23,
%T A319681 23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,42,43,44,
%U A319681 45,46,47,48,49,50,51,52,53,53,54,55,49,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,75,76,77,78,79,80,81
%N A319681 Restricted growth sequence transform of A319680.
%C A319681 For all i, j: a(i) = a(j) => A291784(i) = A291784(j).
%H A319681 Antti Karttunen, <a href="/A319681/b319681.txt">Table of n, a(n) for n = 1..65537</a>
%o A319681 (PARI)
%o A319681 up_to = 65537;
%o A319681 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 A319681 A019565(n) = {my(j,v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
%o A319681 A319680(n) = { my(m=1); fordiv(n,d,if((1==moebius(n/d)), m *= A019565(d))); m; };
%o A319681 v319681 = rgs_transform(vector(up_to,n,A319680(n)));
%o A319681 A319681(n) = v319681[n];
%Y A319681 Cf. A319680, A319682.
%K A319681 nonn
%O A319681 1,2
%A A319681 _Antti Karttunen_, Sep 29 2018