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A080322 Determinant of the n X n tridiagonal matrix M with the elements on the diagonals equal to 1, except M(n,n-1)=M(n-1,n)=n. 0
-3, -9, -1, 24, 36, 1, -63, -81, -1, 120, 144, 1, -195, -225, -1, 288, 324, 1, -399, -441, -1, 528, 576, 1, -675, -729, -1, 840, 900, 1, -1023, -1089, -1, 1224, 1296, 1, -1443, -1521, -1, 1680, 1764, 1, -1935, -2025, -1, 2208, 2304, 1, -2499, -2601, -1, 2808, 2916, 1, -3135, -3249, -1, 3480, 3600, 1, -3843 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

COMMENTS

a(n+2)=A010892(n+1)-(n+2)^2*A010892(n)

FORMULA

G.f.: -(3-8x^2+6x^3-3x^4+x^5)/(1-x+x^2)^3

MATHEMATICA

CoefficientList[Series[ -(3-8x^2+6x^3-3x^4+x^5)/(1-x+x^2)^3, {x, 0, 70}], x]

CROSSREFS

Sequence in context: A154572 A165141 A019817 * A126179 A128727 A126177

Adjacent sequences:  A080319 A080320 A080321 * A080323 A080324 A080325

KEYWORD

easy,sign

AUTHOR

Mario Catalani (mario.catalani(AT)unito.it), Feb 14 2003

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Last modified February 16 02:51 EST 2012. Contains 205860 sequences.