A324885 a(1) = 0; for n > 1, a(n) = A001511(A323243(n)).

0, 1, 1, 3, 1, 2, 1, 4, 3, 1, 1, 3, 1, 2, 2, 4, 1, 2, 1, 3, 1, 5, 1, 4, 3, 3, 4, 5, 1, 6, 1, 6, 2, 5, 2, 4, 1, 2, 5, 4, 1, 2, 1, 3, 3, 6, 1, 5, 3, 1, 3, 3, 1, 2, 1, 4, 5, 2, 1, 3, 1, 5, 3, 4, 2, 6, 1, 5, 2, 2, 1, 4, 1, 3, 2, 5, 2, 6, 1, 5, 4, 5, 1, 3, 5, 4, 6, 5, 1, 2, 1, 6, 2, 5, 3, 4, 1, 1, 5, 4, 1, 2, 1, 4, 6

Offset: 1

Author

Antti Karttunen, Mar 28 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
• Index entries for sequences computed from indices in prime factorization
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A001511, A156552, A286357, A323243, A324725, A324813 (positions of terms <= 1), A324817, A324823, A324883.

Programs

PARI

A001511ext(n) = if(!n,n,sign(n)*(1+valuation(n,2))); \\ Like A001511 but gives 0 for 0 and -A001511(-n) for negative numbers.
A324885(n) = A001511ext(A323243(n)); \\ Needs also code from A323243.

Formula

a(1) = 0; for n > 1, a(n) = A001511(A323243(n)).

For n > 1, a(n) = A286357(A156552(n)).