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A286531 Restricted growth sequence of A278531 (prime-signature of A163511).

%I A286531 #10 Jun 02 2018 10:39:26
%S A286531 1,2,3,2,4,3,5,2,6,4,7,3,7,5,5,2,8,6,9,4,10,7,7,3,9,7,11,5,7,5,5,2,12,
%T A286531 8,13,6,14,9,9,4,14,10,15,7,10,7,7,3,13,9,15,7,15,11,11,5,9,7,11,5,7,
%U A286531 5,5,2,16,12,17,8,18,13,13,6,19,14,20,9,14,9,9,4,18,14,21,10,21,15,15,7,14,10,15,7,10,7,7,3,17,13,20,9,21,15,15,7,20,15
%N A286531 Restricted growth sequence of A278531 (prime-signature of A163511).
%H A286531 Antti Karttunen, <a href="/A286531/b286531.txt">Table of n, a(n) for n = 0..65537</a>
%o A286531 (PARI)
%o A286531 rgs_transform(invec) = { my(occurrences = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(occurrences,invec[i]), my(pp = mapget(occurrences, invec[i])); outvec[i] = outvec[pp] , mapput(occurrences,invec[i],i); outvec[i] = u; u++ )); outvec; };
%o A286531 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
%o A286531 A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ Modified from code of _M. F. Hasler_
%o A286531 A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ This function from _Charles R Greathouse IV_, Aug 17 2011
%o A286531 A278222(n) = A046523(A005940(1+n));
%o A286531 A054429(n) = ((3<<#binary(n\2))-n-1); \\ After _M. F. Hasler_, Aug 18 2014
%o A286531 A278531(n) = if(!n,1,A278222(A054429(n)));
%o A286531 write_to_bfile(0,rgs_transform(vector(65538,n,A278531(n-1))),"b286531.txt");
%Y A286531 Cf. A046523, A163511, A286533, A286535, A286219, A286622, A305433, A305434.
%K A286531 nonn,look
%O A286531 0,2
%A A286531 _Antti Karttunen_, May 17 2017