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A303165
Sum of the squarefree differences |q-p| of the parts in the partitions of n into two distinct parts (p,q) where p < q.
1
0, 0, 1, 2, 4, 2, 9, 8, 16, 8, 16, 18, 27, 18, 40, 32, 55, 32, 72, 32, 91, 32, 112, 54, 135, 54, 135, 80, 135, 80, 164, 110, 195, 110, 228, 144, 263, 144, 300, 182, 339, 182, 380, 224, 423, 224, 423, 270, 470, 270, 470, 270, 521, 270, 574, 270, 629, 270, 686
OFFSET
1,4
FORMULA
a(n) = Sum_{i=1..floor((n-1)/2)} (n-2*i) * mu(n-2*i)^2, where mu is the Möbius function (A008683).
MATHEMATICA
Table[Sum[(n - 2 i) MoebiusMu[n - 2 i]^2, {i, Floor[(n - 1)/2]}], {n, 100}]
CROSSREFS
Sequence in context: A058942 A365638 A196759 * A188813 A324958 A353108
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Apr 19 2018
STATUS
approved