A134812 a(n) = 2a(n-2) + 4a(n-3), n >= 3.

0, 1, -1, 1, 2, -2, 8, 4, 8, 40, 32, 112, 224, 352, 896, 1600, 3200, 6784, 12800, 26368, 52736, 103936, 210944, 418816, 837632, 1681408, 3350528, 6713344, 13426688, 26828800, 53706752, 107364352, 214728704, 429555712, 858914816, 1718026240, 3436052480, 6871711744, 13744209920

Offset: 0

Author

Paul Curtz, Jan 28 2008

Keywords

• sign
• easy

Links

• Joshua Zucker, Table of n, a(n) for n = 0..60
• Index entries for linear recurrences with constant coefficients, signature (0,2,4).

Crossrefs

Cf. A038521.

Programs

Mathematica

CoefficientList[Series[x*(-1 + x + x^2) / ( (2*x-1)*(2*x^2 + 2*x + 1) ),{x,0,38}],x] (* James C. McMahon, Apr 11 2025 *)

Formula

G.f.: x*(-1 + x + x^2) / ( (2*x-1)*(2*x^2 + 2*x + 1) ). - R. J. Mathar, Aug 11 2012

20*a(n) = 2^n - 6*A078069(n), n>0. - R. J. Mathar, Aug 11 2012

Extensions

More terms from Joshua Zucker, Feb 23 2008