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A280250 Sum of the smaller parts of the partitions of 2n into 2 squarefree parts. 4
1, 3, 4, 6, 8, 14, 11, 17, 16, 32, 27, 39, 39, 58, 47, 61, 65, 93, 67, 95, 80, 130, 94, 142, 106, 203, 130, 189, 151, 232, 165, 246, 187, 311, 235, 362, 260, 389, 259, 377, 283, 442, 306, 473, 367, 511, 407, 530, 395, 625, 458, 673, 493, 801, 507, 782, 548, 842, 590, 901 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..60.

Index entries for sequences related to partitions

FORMULA

a(n) = Sum_{i=1..n} i * mu(i)^2 * mu(2*n-i)^2, where mu is the Möbius function (A008683).

a(n) = A280252(n) - A280251(n).

MAPLE

with(numtheory): A280250:=n->sum(i*mobius(i)^2*mobius(2*n-i)^2, i=1..n): seq(A280250(n), n=1..100);

CROSSREFS

Cf. A008683, A185297, A280226, A280251, A280252.

Sequence in context: A244607 A136483 A240494 * A004713 A050475 A340770

Adjacent sequences:  A280247 A280248 A280249 * A280251 A280252 A280253

KEYWORD

nonn,easy

AUTHOR

Wesley Ivan Hurt, Dec 29 2016

STATUS

approved

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Last modified February 25 12:28 EST 2021. Contains 341606 sequences. (Running on oeis4.)