OFFSET
0,3
COMMENTS
Convolution of A000129(n+1) and (n+1)*(-1)^n.
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,4,4,1).
FORMULA
G.f.: 1/((1-2x-x^2)(1+2x+x^2)); a(n)=4a(n-2)+4a(n-3)+a(n-4); a(n)=sum{k=0..floor(n/2), C(n-k, k)2^(n-2k)*(1+(-1)^(n-k))/2}.
a(n) = A000129(n+1)/2 +(n+1)*(-1)^n/2. - R. J. Mathar, Sep 20 2012
MATHEMATICA
LinearRecurrence[{0, 4, 4, 1}, {1, 0, 4, 4}, 30] (* Harvey P. Dale, May 24 2014 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Nov 08 2005
STATUS
approved