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A304113
Restricted growth sequence transform of A278263(n) = A046523(A064413(n)), a filter based on the prime signature of EKG-sequence.
4
1, 2, 3, 4, 2, 3, 5, 6, 4, 2, 4, 5, 4, 2, 4, 7, 8, 5, 4, 2, 4, 6, 9, 3, 4, 5, 4, 2, 4, 10, 11, 4, 2, 4, 9, 4, 2, 4, 5, 7, 5, 4, 2, 4, 12, 5, 5, 7, 7, 3, 5, 13, 4, 4, 9, 4, 2, 4, 9, 4, 2, 4, 14, 15, 5, 4, 2, 4, 5, 9, 5, 12, 4, 2, 4, 8, 13, 4, 7, 4, 2, 4, 13, 4, 4, 10, 5, 4, 2, 4, 16, 5, 4, 7, 9, 5, 9, 14, 4, 2, 4, 9, 9, 12, 5
OFFSET
1,2
COMMENTS
For all i, j: a(i) = a(j) => A064742(i) = A064742(j).
For all i, j: a(i) = a(j) => A065203(i) = A065203(j).
PROG
(PARI)
\\ Needs also code for A064413:
write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
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; };
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
write_to_bfile(1, rgs_transform(vector(65539, n, A278263(n))), "b304113.txt");
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 17 2018
STATUS
approved