A318832 Restricted growth sequence transform of A278222(A000203(n)).

1, 2, 1, 3, 2, 2, 1, 4, 5, 6, 2, 3, 3, 2, 2, 7, 6, 8, 6, 9, 1, 6, 2, 4, 7, 9, 6, 3, 4, 6, 1, 10, 2, 11, 2, 12, 5, 4, 3, 13, 9, 2, 5, 9, 8, 6, 2, 7, 8, 14, 6, 5, 11, 4, 6, 4, 6, 13, 4, 9, 7, 2, 5, 15, 9, 6, 6, 10, 2, 6, 6, 11, 9, 8, 7, 5, 2, 9, 6, 14, 16, 10, 9, 3, 11, 6, 4, 13, 13, 14, 3, 9, 1, 6, 4, 10, 5, 17, 8, 12, 11, 11, 5, 13, 2

Offset: 1

Author

Antti Karttunen, Sep 04 2018

Keywords

• nonn

Comments

Sequence allots a distinct value for each distinct multiset formed from the lengths of 1-runs in the binary representation of A000203(n).

For all i, j: a(i) = a(j) => A175548(i) = A175548(j).

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203, A278222.

Cf. also A286622, A304101, A318831.

Programs

PARI

up_to = 65537;
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; };
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ From A046523
A278222(n) = A046523(A005940(1+n));
v318832 = rgs_transform(vector(up_to,n,A278222(sigma(n))));
A318832(n) = v318832[n];