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.

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

Author

Antti Karttunen, Mar 01 2018

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537

Crossrefs

Cf. A009194, A046523, A286570.

Cf. also A300223, A300226, A300229, A300231, A300232, A300233, A300235.

Programs

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");