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A078048
Expansion of (1-x)/(1+x+2*x^2-2*x^3).
0
1, -2, 0, 6, -10, -2, 34, -50, -22, 190, -246, -178, 1050, -1186, -1270, 5742, -5574, -8450, 31082, -25330, -53734, 166558, -109750, -330834, 883450, -441282, -1987286, 4636750, -1544742, -11703330, 24066314, -3749138, -67790150, 123421054, 4660970, -387083378, 624603546
OFFSET
0,2
FORMULA
a(0) = 1, a(1) = -2, a(2) = 0, a(n) = -a(n-1) - 2*a(n-2) + 2*a(n-3) for n > 2. - Harvey P. Dale, Dec 11 2011
MATHEMATICA
CoefficientList[Series[(1-x)/(1+x+2x^2-2x^3), {x, 0, 40}], x] (* or *) LinearRecurrence[{-1, -2, 2}, {1, -2, 0}, 40] (* Harvey P. Dale, Dec 11 2011 *)
PROG
(PARI) Vec((1-x)/(1+x+2*x^2-2*x^3) + O(x^50)) \\ Jinyuan Wang, Apr 07 2020
CROSSREFS
First differences of A077977.
Sequence in context: A175478 A011123 A087464 * A362186 A335061 A350462
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved