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A300230
Restricted growth sequence transform of A286570, combining A009194(n) and A046523(n), i.e., gcd(n,sigma(n)) and the prime signature of n.
10
1, 2, 2, 3, 2, 4, 2, 5, 3, 6, 2, 7, 2, 6, 8, 9, 2, 10, 2, 11, 12, 6, 2, 13, 3, 6, 5, 14, 2, 15, 2, 16, 8, 6, 12, 17, 2, 6, 12, 18, 2, 15, 2, 7, 10, 6, 2, 19, 3, 20, 8, 11, 2, 21, 12, 22, 12, 6, 2, 23, 2, 6, 20, 24, 12, 15, 2, 11, 8, 25, 2, 26, 2, 6, 20, 7, 12, 15, 2, 27, 9, 6, 2, 28, 12, 6, 8, 29, 2, 30, 31, 7, 12, 6, 32, 33, 2, 20, 10, 17, 2, 15, 2, 34, 35
OFFSET
1,2
LINKS
PROG
(PARI)
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; };
write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
A009194(n) = gcd(n, sigma(n));
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ This function from A046523
A286570(n) = (1/2)*(2 + ((A046523(n)+A009194(n))^2) - A046523(n) - 3*A009194(n));
write_to_bfile(1, rgs_transform(vector(65537, n, A286570(n))), "b300230.txt");
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 01 2018
STATUS
approved