|
Search: id:A028860
|
|
|
| A028860 |
|
a(n+2) = 2 a(n+1) + 2 a(n). |
|
+0
6
|
|
| -1, 1, 0, 2, 4, 12, 32, 88, 240, 656, 1792, 4896, 13376, 36544, 99840, 272768, 745216, 2035968, 5562368, 15196672, 41518080, 113429504, 309895168, 846649344, 2313089024, 6319476736, 17265131520
(list; graph; listen)
|
|
|
OFFSET
|
0,4
|
|
|
LINKS
|
INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 924
Tanya Khovanova, Recursive Sequences
Index entries for sequences related to linear recurrences with constant coefficients
|
|
FORMULA
|
a(n) = 4*A028859(n-4), for n>3.
G.f.: -(1-3x)/(1-2x-2x^2). a(n) = 3*A002605(n-1) -A002605(n). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 27 2008]
|
|
MATHEMATICA
|
(With a different offset) M = {{0, 2}, {1, 2}} v[1] = {0, 1} v[n_] := v[n] = M.v[n - 1] a = Table[Abs[v[n][[1]]], {n, 1, 50}] - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), May 29 2005
|
|
CROSSREFS
|
Sequence in context: A141312 A148192 A109388 this_sequence A152035 A026151 A025178
Adjacent sequences: A028857 A028858 A028859 this_sequence A028861 A028862 A028863
|
|
KEYWORD
|
sign
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com). Edited by N. J. A. Sloane, Apr 11 2009
|
|
|
Search completed in 0.002 seconds
|
