A103749 Expansion of x*(1+2*x)/(1+x+x^2-2*x^3).

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

Author

Roger L. Bagula, Mar 28 2005

Keywords

• sign
• easy

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 .

Links

• Richard Kenyon, The Construction of Self-Similar Tilings, arXiv:math.MG/9405210
• Index entries for linear recurrences with constant coefficients, signature (-1,-1,2).

Crossrefs

Cf. A099206.

Programs

Mathematica

LinearRecurrence[{-1,-1,2},{0,1,1},50] (* Harvey P. Dale, Jul 23 2013 *)

Formula

a(n) = -a(n-1)-a(n-2)+2*a(n-3) = A077975(n-1)+2*A077975(n-2).

Extensions

Edited, replaced by signed variant by the Assoc. Eds. of the OEIS - Jul 31 2010