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 A284829 #7 Apr 05 2017 04:46:48
%S A284829 1,3,5,9,13,23,30,45,64,89,118,165,211,282,369,475,606,779,978,1236,
%T A284829 1547,1922,2375,2936,3602,4403,5362,6506,7864,9493,11399,13661,16317,
%U A284829 19443,23122,27415,32418,38268,45065,52968,62125,72742,84969,99112,115409,134139,155665,180368,208658,241051
%N A284829 Expansion of Sum_{i>=1} mu(i)^2*x^i/(1 - x^i) * Product_{j>=i} 1/(1 - mu(j)^2*x^j), where mu() is the Moebius function (A008683).
%C A284829 Total number of smallest parts in all partitions of n into squarefree parts (A005117).
%H A284829 <a href="/index/Par#partN">Index entries for related partition-counting sequences</a>
%F A284829 G.f.: Sum_{i>=1} mu(i)^2*x^i/(1 - x^i) * Product_{j>=i} 1/(1 - mu(j)^2*x^j).
%e A284829 a(5) = 13 because we have [5], [3, 2], [3, 1, 1], [2, 2, 1], [2, 1, 1, 1], [1, 1, 1, 1, 1] and 1 + 1 + 2 + 1 + 3 + 5 = 13.
%t A284829 nmax = 50; Rest[CoefficientList[Series[Sum[MoebiusMu[i]^2 x^i/(1 - x^i) Product[1/(1 - MoebiusMu[j]^2 x^j), {j, i, nmax}], {i, 1, nmax}], {x, 0, nmax}], x]]
%o A284829 (PARI) x='x+O('x^50); Vec(sum(i=1, 50, moebius(i)^2*x^i/(1 - x^i) * prod(j=i, 50, 1/(1 - moebius(j)^2*x^j)))) \\ _Indranil Ghosh_, Apr 04 2017
%Y A284829 Cf. A005117, A008683, A073576, A092268, A092269, A195820, A281572.
%K A284829 nonn
%O A284829 1,2
%A A284829 _Ilya Gutkovskiy_, Apr 03 2017