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 A308907 #7 Jun 29 2019 23:02:59
%S A308907 0,0,0,0,0,0,1,1,2,2,4,6,10,10,14,18,26,28,37,41,57,62,77,87,113,122,
%T A308907 152,170,213,230,279,307,376,402,471,516,622,661,768,830,978,1041,
%U A308907 1194,1282,1492,1586,1804,1932,2217,2340,2632,2815,3195,3380,3780,4026
%N A308907 Sum of the fifth largest parts in the partitions of n into 6 squarefree parts.
%H A308907 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A308907 a(n) = Sum_{m=1..floor(n/6)} Sum_{l=m..floor((n-m)/5)} Sum_{k=l..floor((n-l-m)/4)} Sum_{j=k..floor((n-k-l-m)/3)} Sum_{i=j..floor((n-j-k-l-m)/2)} mu(m)^2 * mu(l)^2 * mu(k)^2 * mu(j)^2 * mu(i)^2 * mu(n-i-k-j-l-m)^2 * l, where mu is the Möbius function (A008683).
%F A308907 a(n) = A308903(n) - A308906(n) - A308908(n) - A308909(n) - A308910(n) - A308911(n).
%t A308907 Table[Sum[Sum[Sum[Sum[Sum[l*MoebiusMu[i]^2*MoebiusMu[j]^2*MoebiusMu[k]^2* MoebiusMu[l]^2*MoebiusMu[m]^2*MoebiusMu[n - i - j - k - l - m]^2, {i, j, Floor[(n - j - k - l - m)/2]}], {j, k, Floor[(n - k - l - m)/3]}], {k, l, Floor[(n - l - m)/4]}], {l, m, Floor[(n - m)/5]}], {m, Floor[n/6]}], {n, 0, 50}]
%Y A308907 Cf. A008683, A308902, A308903, A308906, A308908, A308909, A308910, A308911.
%K A308907 nonn
%O A308907 0,9
%A A308907 _Wesley Ivan Hurt_, Jun 29 2019