OFFSET
1,30
COMMENTS
If x and y are factorizations of the same integer and it is possible to produce x by further factoring the factors of y, flattening, and sorting, then x <= y.
FORMULA
Product_{k>=2} 1/(1-a(n)/n^s) = 1+P(s), Re(s)>1, where P(s) is the prime zeta function. - Tian Vlasic, Jan 25 2024
EXAMPLE
The factorizations of 60 followed by their Moebius values are the following. The second column sums to 0, as required.
(2*2*3*5) -> -3
(2*2*15) -> 1
(2*3*10) -> 2
(2*5*6) -> 2
(2*30) -> -1
(3*4*5) -> 2
(3*20) -> -1
(4*15) -> -1
(5*12) -> -1
(6*10) -> -1
(60) -> 1
CROSSREFS
KEYWORD
sign
AUTHOR
Gus Wiseman, Jul 22 2018
STATUS
approved