|
Search: id:A084222
|
|
|
| A084222 |
|
a(n)=-2a(n-1)+3a(n-2), with a(0)=1, a(1)=2. |
|
+0
3
|
|
| 1, 2, -1, 8, -19, 62, -181, 548, -1639, 4922, -14761, 44288, -132859, 398582, -1195741, 3587228, -10761679, 32285042, -96855121, 290565368, -871696099, 2615088302, -7845264901, 23535794708, -70607384119, 211822152362, -635466457081, 1906399371248
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
FORMULA
|
Binomial transform is A084221.
a(n)=(5-(-3)^n)/4; G.f.: (1+4x)/((1-x)(1+3x)); E.g.f. : (5exp(x)-exp(-3x))/4.
For n > 1, |a(n) - a(n+1)| = 3^n. - Amarnath Murthy and Meenakshi Srikanth (amarnath_murthy(AT)yahoo.com), Jul 15 2003; corrected by Philippe DELEHAM, Dec 16 2007
|
|
CROSSREFS
|
Adjacent sequences: A084219 A084220 A084221 this_sequence A084223 A084224 A084225
Sequence in context: A013124 A012966 A009828 this_sequence A052312 A110742 A013123
|
|
KEYWORD
|
easy,sign
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), May 21 2003
|
|
|
Search completed in 0.002 seconds
|
