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A078061 Expansion of (1-x)/(1+2*x+x^3). 0
1, -3, 6, -13, 29, -64, 141, -311, 686, -1513, 3337, -7360, 16233, -35803, 78966, -174165, 384133, -847232, 1868629, -4121391, 9090014, -20048657, 44218705, -97527424, 215103505, -474425715, 1046378854, -2307861213, 5090148141, -11226675136, 24761211485, -54612571111, 120451817358 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n)=(-1)^n*sum{k=0..n, C(n-k,floor(k/2))*2^(n-k-floor(k/2))}. [From Paul Barry (pbarry(AT)wit.ie), Oct 20 2009]

CROSSREFS

Sequence in context: A106496 A052933 A071014 * A018909 A093128 A005313

Adjacent sequences:  A078058 A078059 A078060 * A078062 A078063 A078064

KEYWORD

sign

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Nov 17 2002

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Last modified February 16 04:47 EST 2012. Contains 205860 sequences.