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A103749
Expansion of x*(1+2*x)/(1+x+x^2-2*x^3).
0
0, 1, 1, -2, 3, 1, -8, 13, -3, -26, 55, -35, -72, 217, -215, -146, 795, -1079, -8, 2677, -4827, 2134, 8047, -19835, 16056, 19873, -75599, 87838, 27507, -266543, 414712, -93155, -854643, 1777222, -1108889, -2377619, 7040952, -6881111, -4915079, 25878094, -34725237, -983015
OFFSET
0,4
COMMENTS
Insert n=3, p=2, q=-1 and r=1 in Kenyon's characteristic polynomial x^n-p*x^(n-1)+q*x+r=0 .
FORMULA
a(n) = -a(n-1)-a(n-2)+2*a(n-3) = A077975(n-1)+2*A077975(n-2).
MATHEMATICA
LinearRecurrence[{-1, -1, 2}, {0, 1, 1}, 50] (* Harvey P. Dale, Jul 23 2013 *)
CROSSREFS
Cf. A099206.
Sequence in context: A301332 A110292 A138672 * A098435 A096294 A157963
KEYWORD
sign,easy
AUTHOR
Roger L. Bagula, Mar 28 2005
EXTENSIONS
Edited, replaced by signed variant by the Assoc. Eds. of the OEIS - Jul 31 2010
STATUS
approved