|
|
A166249
|
|
a(n) = 2*a(n-1) - a(n-3) + 2*a(n-4) for n>3, a(0)=a(1)=1, a(2)=0, a(3)=2.
|
|
2
|
|
|
1, 1, 0, 2, 5, 12, 22, 43, 84, 170, 341, 684, 1366, 2731, 5460, 10922, 21845, 43692, 87382, 174763, 349524, 699050, 1398101, 2796204, 5592406, 11184811, 22369620, 44739242, 89478485, 178956972, 357913942, 715827883, 1431655764, 2863311530
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,4
|
|
LINKS
|
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2,0,-1,2).
|
|
FORMULA
|
From R. J. Mathar, Nov 09 2009: (Start)
G.f.: (1-x+3*x^3-2*x^2)/((1-2*x)*(1+x)*(x^2-x+1)).
a(n) = A001045(n) + A010892(n+1). (End)
|
|
MATHEMATICA
|
LinearRecurrence[{2, 0, -1, 2}, {1, 1, 0, 2}, 100] (* G. C. Greubel, May 08 2016 *)
|
|
CROSSREFS
|
Sequence in context: A215183 A086734 A123647 * A326762 A116711 A247658
Adjacent sequences: A166246 A166247 A166248 * A166250 A166251 A166252
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
Paul Curtz, Oct 10 2009
|
|
EXTENSIONS
|
Edited by N. J. A. Sloane, Oct 13 2009
Extended by R. J. Mathar, Nov 09 2009
|
|
STATUS
|
approved
|
|
|
|