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A294232
Number of partitions of n into two parts with smaller part squarefree and larger part nonsquarefree.
1
0, 0, 0, 0, 1, 1, 1, 0, 1, 2, 2, 1, 2, 3, 3, 1, 2, 2, 3, 1, 3, 3, 4, 1, 3, 4, 4, 3, 5, 6, 6, 3, 5, 5, 6, 1, 5, 6, 6, 2, 5, 6, 5, 2, 5, 8, 8, 3, 6, 8, 9, 3, 7, 7, 10, 4, 7, 7, 9, 4, 8, 9, 9, 5, 9, 10, 10, 4, 10, 10, 12, 2, 10, 10, 11, 5, 11, 13, 12, 6
OFFSET
1,10
FORMULA
a(n) = Sum_{i=1..floor(n/2)} (1 - mu(n-i)^2) * mu(i)^2, where mu is the Möbius function (A008683).
MATHEMATICA
Table[Sum[(1 - MoebiusMu[n - k]^2) (MoebiusMu[k]^2), {k, Floor[n/2]}], {n, 80}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Oct 25 2017
STATUS
approved