|
|
A136326
|
|
a(n) = a(n-1) + 4a(n-2) - 4a(n-3).
|
|
3
|
|
|
1, 2, 4, 9, 17, 37, 69, 149, 277, 597, 1109, 2389, 4437, 9557, 17749, 38229, 70997, 152917, 283989, 611669, 1135957, 2446677, 4543829, 9786709, 18175317, 39146837, 72701269, 156587349, 290805077, 626349397, 1163220309, 2505397589, 4652881237, 10021590357
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
G.f.: (1+x-2*x^2+x^3)/(1-x-4*x^2+4*x^3). - Harvey P. Dale, Nov 27 2014
|
|
MATHEMATICA
|
Join[{1}, LinearRecurrence[{1, 4, -4}, {2, 4, 9}, 40]] (* Harvey P. Dale, Nov 27 2014 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|