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A304730 Restricted growth sequence transform of A046523(A281978(n)).

%I A304730 #7 May 19 2018 17:38:42
%S A304730 1,2,3,4,3,4,3,5,4,6,7,6,5,8,2,6,5,9,10,11,9,12,5,6,7,13,14,15,16,17,
%T A304730 16,15,14,18,19,20,13,21,13,22,20,23,24,23,22,25,26,27,28,29,28,27,19,
%U A304730 26,20,22,18,22,13,21,11,30,31,32,33,34,35,36,37,38,31,39,2,8,5,9,5,6,7,16,6,17,16,31,12,40,8,31,12,31,11,30,31,39,16,17,16
%N A304730 Restricted growth sequence transform of A046523(A281978(n)).
%H A304730 Antti Karttunen, <a href="/A304730/b304730.txt">Table of n, a(n) for n = 1..65535</a>
%o A304730 (PARI)
%o A304730 up_to = (2^16)+1;
%o A304730 v281978 = vector(1+up_to); v281978[1] = 1;
%o A304730 minverses = Map(); mapput(minverses,1,1);
%o A304730 least_unused_proper_divisor(inverses,n) = { fordiv(n,d,if((d<n) && !mapisdefined(minverses,d), return(d))); (0); }
%o A304730 prev=1; n = 2; while(n < up_to+1, try = prev; while(mapisdefined(minverses,try) || !(pd = least_unused_proper_divisor(minverses,try)), try += prev); mapput(minverses,v281978[n] = try,n); mapput(minverses,v281978[1+n] = pd,1+n); prev = pd; n += 2);
%o A304730 A281978(n) = v281978[n];
%o A304730 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 A304730 A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ From A046523
%o A304730 v304730 = rgs_transform(vector(65535,n,A046523(A281978(n))));
%o A304730 A304730(n) = v304730[n];
%Y A304730 Cf. A046523, A281978.
%Y A304730 Compare also to the scatter plots of A304098, A304729 and A304732.
%Y A304730 Cf. also A304743.
%K A304730 nonn
%O A304730 1,2
%A A304730 _Antti Karttunen_, May 19 2018