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Restricted growth sequence transform of A278222(A304083(n)).
4

%I #5 May 12 2018 14:45:02

%S 1,2,3,2,4,3,2,5,6,4,3,2,7,5,7,5,8,6,4,3,2,9,7,5,10,7,5,9,7,5,11,12,7,

%T 13,9,4,3,2,8,6,7,5,14,9,7,5,13,10,7,5,10,7,14,9,7,5,15,11,15,11,16,

%U 15,11,9,7,12,8,6,4,3,2,17,14,9,7,5,18,14,9,7,5,19,13,9,7,5,20,15,11,18,13,10,7,5,21,15,11,21,15,11,17,14,9,7,5

%N Restricted growth sequence transform of A278222(A304083(n)).

%H Antti Karttunen, <a href="/A304088/b304088.txt">Table of n, a(n) for n = 0..65537</a>

%F For all i, j: a(i) = a(j) => A304089(i) = A304089(j).

%o (PARI)

%o \\ Needs also code from A304083:

%o 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 write_to_bfile(start_offset,vec,bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }

%o A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };

%o A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523

%o A278222(n) = A046523(A005940(1+n));

%o write_to_bfile(0,rgs_transform(vector(65538,n,A278222(A304083(n-1)))),"b304088.txt");

%Y Cf. A278222, A304083, A304089.

%Y Cf. also A303779.

%K nonn

%O 0,2

%A _Antti Karttunen_, May 06 2018