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A286448 Restricted growth sequence computed for A252748 (= A003961(n) - 2*n).

%I A286448 #11 May 13 2017 17:19:53
%S A286448 1,1,1,2,3,4,3,5,6,2,7,8,7,9,9,10,11,12,11,13,14,15,16,17,1,1,18,19,
%T A286448 20,21,22,23,1,24,6,25,26,27,6,28,29,30,29,31,32,15,33,34,13,35,27,10,
%U A286448 36,37,38,39,2,40,41,42,43,44,45,46,24,47,48,49,6,50,51,52,53,22,54,55,24,56,57,58,59,60,61,62,63,64,38,65,66,67,9,68,1,69,69,70
%N A286448 Restricted growth sequence computed for A252748 (= A003961(n) - 2*n).
%H A286448 Antti Karttunen, <a href="/A286448/b286448.txt">Table of n, a(n) for n = 1..10000</a>
%o A286448 (PARI)
%o A286448 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 A286448 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
%o A286448 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ This function from _Michel Marcus_
%o A286448 A252748(n) = (A003961(n) - (2*n));
%o A286448 write_to_bfile(1,rgs_transform(vector(10000,n,A252748(n))),"b286448.txt");
%Y A286448 Cf. A003961, A252748, A286449, A286450.
%K A286448 nonn
%O A286448 1,4
%A A286448 _Antti Karttunen_, May 13 2017