A280316 Sum of squares of parts of the partitions of 2n into two squarefree parts.

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

Links

Table of n, a(n) for n=1..43.

Index entries for sequences related to partitions

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

Cf. A008683, A280226, A280320, A280322.

Sequence in context: A072278 A296266 A365493 * A131538 A009820 A304933

Adjacent sequences: A280313 A280314 A280315 * A280317 A280318 A280319

Keyword

nonn,easy

Author

Wesley Ivan Hurt, Dec 31 2016

Status

approved