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A302604
Number of partitions of n into two parts such that the positive difference of the parts is squarefree.
2
0, 0, 1, 1, 2, 1, 3, 2, 4, 2, 4, 3, 5, 3, 6, 4, 7, 4, 8, 4, 9, 4, 10, 5, 11, 5, 11, 6, 11, 6, 12, 7, 13, 7, 14, 8, 15, 8, 16, 9, 17, 9, 18, 10, 19, 10, 19, 11, 20, 11, 20, 11, 21, 11, 22, 11, 23, 11, 24, 12, 25, 12, 26, 13, 26, 13, 27, 14, 28, 14, 29, 15, 30
OFFSET
1,5
FORMULA
a(n) = Sum_{i=1..floor((n-1)/2)} mu(n-2i)^2, where mu is the Möbius function (A008683).
MATHEMATICA
Table[Sum[(MoebiusMu[(n - 2 i)]^2), {i, Floor[(n-1)/2]}], {n, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Apr 10 2018
STATUS
approved