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A280316
Sum of squares of parts of the partitions of 2n into two squarefree parts.
3
2, 18, 44, 124, 108, 372, 398, 886, 888, 1560, 1642, 2778, 2098, 3440, 2810, 5618, 5350, 9766, 6934, 12382, 9744, 17448, 11112, 20440, 12728, 24050, 19508, 26610, 25270, 36108, 28950, 41020, 31974, 56038, 42490, 74484, 51668, 77210, 52810, 87970, 57074, 105804, 68972
OFFSET
1,1
FORMULA
a(n) = Sum_{i=1..n} (i^2 + (2*n-i)^2) * mu(i)^2 * mu(2*n-i)^2, where mu is the Möbius function (A008683).
a(n) = A280320(n) + A280322(n).
MAPLE
with(numtheory): A280316:=n->add((i^2+(2*n-i)^2) * mobius(i)^2 * mobius(2*n-i)^2, i=1..n): seq(A280316(n), n=1..100);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Dec 31 2016
STATUS
approved