A085277 Expansion of (1+x)^2/((1-2x)(1-3x)).

1, 7, 30, 108, 360, 1152, 3600, 11088, 33840, 102672, 310320, 935568, 2815920, 8466192, 25435440, 76380048, 229287600, 688157712, 2065062960, 6196368528, 18591464880, 55779113232, 167346776880, 502059205008, 1506215363760

Offset

0,2

Comments

Inverse binomial transform of A016208. Binomial transform of A085278.

Links

Table of n, a(n) for n=0..24.

Index entries for linear recurrences with constant coefficients, signature (5,-6).

Formula

a(n)=16*3^n/3+0^n/6-9*2^n/2.

a(0)=1, a(1)=7, a(2)=30, a(n)=5*a(n-1)-6*a(n-2). - Harvey P. Dale, Sep 30 2012

Mathematica

CoefficientList[Series[(1+x)^2/((1-2x)(1-3x)), {x, 0, 30}], x] (* or *) Join[{1}, LinearRecurrence[{5, -6}, {7, 30}, 30]] (* Harvey P. Dale, Sep 30 2012 *)

Crossrefs

Sequence in context: A062455 A364655 A368528 * A269084 A055269 A026631

Adjacent sequences: A085274 A085275 A085276 * A085278 A085279 A085280

Keyword

easy,nonn

Author

Paul Barry, Jun 25 2003

Status

approved