login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A326525 Sum of the eighth largest parts in the partitions of n into 9 squarefree parts. 10
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 4, 5, 8, 9, 14, 18, 24, 28, 39, 46, 60, 69, 90, 105, 133, 149, 189, 216, 264, 297, 364, 412, 494, 553, 661, 743, 877, 972, 1149, 1280, 1493, 1650, 1922, 2126, 2454, 2702, 3107, 3429, 3916, 4291, 4895, 5374, 6086, 6647 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,12
LINKS
FORMULA
a(n) = Sum_{q=1..floor(n/9)} Sum_{p=q..floor((n-q)/8)} Sum_{o=p..floor((n-p-q)/7)} Sum_{m=o..floor((n-o-p-q)/6)} Sum_{l=m..floor((n-m-o-p-q)/5)} Sum_{k=l..floor((n-l-m-o-p-q)/4)} Sum_{j=k..floor((n-k-l-m-o-p-q)/3)} Sum_{i=j..floor((n-j-k-l-m-o-p-q)/2)} mu(q)^2 * mu(p)^2 * mu(o)^2 * mu(m)^2 * mu(l)^2 * mu(k)^2 * mu(j)^2 * mu(i)^2 * mu(n-i-j-k-l-m-o-p-q)^2 * p, where mu is the Möbius function (A008683).
a(n) = A326523(n) - A326524(n) - A326526(n) - A326527(n) - A326528(n) - A326529(n) - A326530(n) - A326531(n) - A326532(n).
MATHEMATICA
Table[Total[Select[IntegerPartitions[n, {9}], AllTrue[#, SquareFreeQ]&][[;; , 8]]], {n, 0, 60}] (* Harvey P. Dale, Jan 30 2024 *)
CROSSREFS
Sequence in context: A304332 A183564 A222707 * A326630 A317810 A308954
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jul 11 2019
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 11:31 EDT 2024. Contains 371792 sequences. (Running on oeis4.)