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A294248 Number of partitions of 2n into two distinct squarefree parts. 2
0, 1, 1, 3, 1, 3, 2, 5, 4, 5, 4, 7, 4, 6, 4, 8, 6, 11, 6, 11, 7, 12, 7, 13, 8, 13, 10, 13, 10, 14, 10, 15, 10, 17, 12, 21, 13, 19, 12, 20, 12, 21, 13, 23, 17, 22, 16, 24, 17, 25, 17, 26, 18, 31, 18, 29, 19, 30, 19, 31, 19, 32, 23, 30, 22, 31, 22, 32, 22, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..70.

Index entries for sequences related to partitions

FORMULA

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

MATHEMATICA

Table[Sum[MoebiusMu[i]^2*MoebiusMu[2 n - i]^2, {i, n - 1}], {n, 80}]

PROG

(PARI) A294248(n)=sum(i=1, n-1, moebius(i)^2*moebius(2*n-i)^2); \\ R. J. Cano, Oct 25 2017

CROSSREFS

Cf. A008683, A280226.

Sequence in context: A126208 A287863 A126088 * A085671 A126324 A035557

Adjacent sequences:  A294245 A294246 A294247 * A294249 A294250 A294251

KEYWORD

nonn,easy

AUTHOR

Wesley Ivan Hurt, Oct 25 2017

STATUS

approved

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Last modified August 13 22:57 EDT 2020. Contains 336473 sequences. (Running on oeis4.)