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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.

A308840 Number of partitions of n into 5 squarefree parts.

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%I A308840 #10 Sep 16 2019 21:32:04
%S A308840 0,0,0,0,0,1,1,2,2,4,5,7,7,10,11,15,15,20,22,28,29,37,39,48,49,61,63,
%T A308840 76,77,93,97,113,115,135,140,161,164,190,196,224,228,261,269,304,308,
%U A308840 351,360,404,412,462,475,528,538,597,612,675,685,759,774,849
%N A308840 Number of partitions of n into 5 squarefree parts.
%H A308840 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A308840 a(n) = Sum_{l=1..floor(n/5)} Sum_{k=l..floor((n-l)/4)} Sum_{j=k..floor((n-k-l)/3)} Sum_{i=j..floor((n-j-k-l)/2)} mu(l)^2 * mu(k)^2 * mu(j)^2 * mu(i)^2 * mu(n-i-j-k-l)^2, where mu is the Möbius function (A008683).
%F A308840 a(n) = A308839(n)/n.
%e A308840 The partitions of n into 5 parts for n = 10, 11, ..
%e A308840                                                        1+1+1+1+10
%e A308840                                                         1+1+1+2+9
%e A308840                                                         1+1+1+3+8
%e A308840                                                         1+1+1+4+7
%e A308840                                                         1+1+1+5+6
%e A308840                                             1+1+1+1+9   1+1+2+2+8
%e A308840                                             1+1+1+2+8   1+1+2+3+7
%e A308840                                             1+1+1+3+7   1+1+2+4+6
%e A308840                                             1+1+1+4+6   1+1+2+5+5
%e A308840                                             1+1+1+5+5   1+1+3+3+6
%e A308840                                 1+1+1+1+8   1+1+2+2+7   1+1+3+4+5
%e A308840                                 1+1+1+2+7   1+1+2+3+6   1+1+4+4+4
%e A308840                                 1+1+1+3+6   1+1+2+4+5   1+2+2+2+7
%e A308840                     1+1+1+1+7   1+1+1+4+5   1+1+3+3+5   1+2+2+3+6
%e A308840                     1+1+1+2+6   1+1+2+2+6   1+1+3+4+4   1+2+2+4+5
%e A308840                     1+1+1+3+5   1+1+2+3+5   1+2+2+2+6   1+2+3+3+5
%e A308840         1+1+1+1+6   1+1+1+4+4   1+1+2+4+4   1+2+2+3+5   1+2+3+4+4
%e A308840         1+1+1+2+5   1+1+2+2+5   1+1+3+3+4   1+2+2+4+4   1+3+3+3+4
%e A308840         1+1+1+3+4   1+1+2+3+4   1+2+2+2+5   1+2+3+3+4   2+2+2+2+6
%e A308840         1+1+2+2+4   1+1+3+3+3   1+2+2+3+4   1+3+3+3+3   2+2+2+3+5
%e A308840         1+1+2+3+3   1+2+2+2+4   1+2+3+3+3   2+2+2+2+5   2+2+2+4+4
%e A308840         1+2+2+2+3   1+2+2+3+3   2+2+2+2+4   2+2+2+3+4   2+2+3+3+4
%e A308840         2+2+2+2+2   2+2+2+2+3   2+2+2+3+3   2+2+3+3+3   2+3+3+3+3
%e A308840 --------------------------------------------------------------------------
%e A308840   n  |     10          11          12          13          14        ...
%e A308840 --------------------------------------------------------------------------
%e A308840 a(n) |      5           7           7          10          11        ...
%e A308840 --------------------------------------------------------------------------
%e A308840 - _Wesley Ivan Hurt_, Sep 16 2019
%t A308840 Table[Sum[Sum[Sum[Sum[MoebiusMu[l]^2*MoebiusMu[k]^2*MoebiusMu[j]^2* MoebiusMu[i]^2*MoebiusMu[n - i - j - k - l]^2, {i, j, Floor[(n - j - k - l)/2]}], {j, k, Floor[(n - k - l)/3]}], {k, l, Floor[(n - l)/4]}], {l, Floor[n/5]}], {n, 0, 80}]
%Y A308840 Cf. A008683, A308839.
%K A308840 nonn
%O A308840 0,8
%A A308840 _Wesley Ivan Hurt_, Jun 28 2019