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A294104
Sum of the differences of the larger and smaller parts in the partitions of n into two squarefree parts or two nonsquarefree parts.
1
0, 0, 1, 2, 1, 4, 8, 12, 8, 4, 10, 24, 22, 20, 29, 54, 33, 40, 31, 72, 37, 70, 54, 114, 68, 62, 74, 116, 97, 62, 114, 182, 136, 126, 147, 292, 175, 134, 180, 330, 214, 182, 227, 412, 273, 190, 209, 460, 343, 202, 156, 468, 392, 380, 156, 518, 394, 490, 303
OFFSET
1,4
FORMULA
a(n) = Sum_{i=1..floor(n/2)} (n - 2i) * [A008966(i) = A008966(n-i)], where [] is the Iverson bracket.
MAPLE
f:= n -> add(n-2*i, i = select(t -> numtheory:-issqrfree(t)=numtheory:-issqrfree(n-t), [$1..n/2])):
map(f, [$1..100]); # Robert Israel, Jun 12 2020
MATHEMATICA
Table[Sum[(n - 2 k) KroneckerDelta[MoebiusMu[k]^2, MoebiusMu[ n - k]^2], {k, Floor[n/2]}], {n, 80}]
CROSSREFS
Sequence in context: A156817 A008301 A363386 * A294061 A113820 A319479
KEYWORD
nonn,easy,look
AUTHOR
Wesley Ivan Hurt, Oct 22 2017
STATUS
approved