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A120582 Hankel transform of sum{k=0..floor(n/2), C(2k,k)}. 1
1, 2, 0, 0, -16, -32, -64, -128, 0, 0, 1024, 2048, 4096, 8192, 0, 0, -65536, -131072, -262144, -524288, 0, 0, 4194304, 8388608, 16777216, 33554432, 0, 0, -268435456, -536870912, -1073741824, -2147483648, 0, 0, 17179869184, 34359738368, 68719476736, 137438953472, 0, 0, -1099511627776 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Hankel transform of A100066(n+1).

FORMULA

a(n)=2^n*(-sqrt(3)cos(5*pi*n/6+pi/3)/6+(sqrt(3)/3-1/2)*sin(5*pi*n/6+pi/3)+(sqrt(3)/3+1/2)*cos(pi*n/6+pi/6)+sqrt(3)*sin(pi*n/6+pi/6)/6);

CROSSREFS

Cf. A120580.

Sequence in context: A158465 A003193 A108474 * A003784 A066294 A020916

Adjacent sequences:  A120579 A120580 A120581 * A120583 A120584 A120585

KEYWORD

easy,sign

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Jun 15 2006

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Last modified February 14 14:07 EST 2012. Contains 205623 sequences.