A099211 a(n)=-2a(n-1)+4a(n-3).

1, -2, 4, -4, 0, 16, -48, 96, -128, 64, 256, -1024, 2304, -3584, 3072, 3072, -20480, 53248, -94208, 106496, 0, -376832, 1179648, -2359296, 3211264, -1703936, -6029312, 24903680, -56623104, 89128960, -78643200, -69206016

Offset

0,2

Links

Table of n, a(n) for n=0..31.

Index entries for linear recurrences with constant coefficients, signature (-2,0,4).

Formula

G.f.: 1/(1+2x-4x^3); a(n)=A099212(n+4)/4.

Crossrefs

Sequence in context: A090132 A199051 A300190 * A261761 A300269 A094225

Adjacent sequences: A099208 A099209 A099210 * A099212 A099213 A099214

Keyword

easy,sign

Author

Paul Barry, Oct 06 2004

Status

approved