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A140412 Determinants of the n X n matrices whose (i,j)-elements are LCM(i^2,j^2). 0
1, -12, 864, -41472, 24883200, 21499084800, -50565847449600, 9708642710323200, -6291200476289433600, -45296643429283921920000, 657707262593202546278400000, 2273036299522107999938150400000, -64536046616031690334243966156800000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

The determinants of the n X n matrices whose (i,j)-elements are LCM(i,j) are given in A060238.

FORMULA

It appears that a(n) = Product[MT2(k) * sfk(k)^2 * mu[sfk(k)), k=1,2,...,n], where MT2(k) is the k-th term of the Moebius transform of the sequence of squares, sfk(k) is the squarefree kernel of k and mu denotes the Moebius function.

CROSSREFS

Cf. A060238.

Sequence in context: A178023 A003748 A203410 * A116225 A159870 A203599

Adjacent sequences:  A140409 A140410 A140411 * A140413 A140414 A140415

KEYWORD

sign

AUTHOR

John W. Layman (layman(AT)math.vt.edu), Jun 17 2008

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.