This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A326526 #11 May 04 2021 14:33:09
%S A326526 0,0,0,0,0,0,0,0,0,1,1,2,2,4,5,8,10,15,19,26,31,43,51,67,78,103,119,
%T A326526 152,172,219,250,308,348,429,486,585,658,794,892,1063,1185,1410,1572,
%U A326526 1847,2053,2407,2670,3095,3425,3964,4380,5030,5532,6344,6974,7939
%N A326526 Sum of the seventh largest parts of the partitions of n into 9 squarefree parts.
%H A326526 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A326526 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 * o, where mu is the Möbius function (A008683).
%F A326526 a(n) = A326523(n) - A326524(n) - A326525(n) - A326527(n) - A326528(n) - A326529(n) - A326530(n) - A326531(n) - A326532(n).
%t A326526 Table[Total[Select[IntegerPartitions[n,{9}],AllTrue[#,SquareFreeQ]&][[All,7]]],{n,0,60}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Dec 05 2020 *)
%Y A326526 Cf. A008683, A326522, A326523, A326524, A326525, A326527, A326528, A326529, A326530, A326531, A326532.
%K A326526 nonn
%O A326526 0,12
%A A326526 _Wesley Ivan Hurt_, Jul 11 2019