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%I #44 Oct 31 2020 13:22:26
%S 1,2,2,1,2,3,3,1,1,3,4,2,1,4,4,2,3,3,4,2,3,4,5,2,1,5,4,2,2,6,5,3,3,3,
%T 6,2,4,7,7,3,3,7,5,3,2,6,7,3,2,5,7,3,3,4,7,4,4,5,7,4,2,8,5,3,4,8,7,4,
%U 5,7,9,3,4,7,7,2,5,9,6,4,3,8,10,4,3,9,10,4,4,6
%N Number of ways to write n as the sum of a squarefree number (A005117) and a square (A000290).
%C Differs from A085263 where the square cannot be zero.
%H Jorge Urroz, <a href="https://arxiv.org/abs/2010.15580">Every integer can be written as a square plus a squarefree</a>, arXiv:2010.15580 [math.NT], 2020.
%o (PARI) a(n) = sum(k=0, n, issquare(k) * issquarefree(n-k));
%Y Cf. A000290, A005117, A085263 (with a positive square).
%K nonn
%O 1,2
%A _Michel Marcus_, Oct 31 2020