|
Search: id:A095364
|
|
|
| A095364 |
|
Number of walks of length n between two adjacent nodes in the cycle graph C_9. |
|
+0
1
|
|
| 1, 0, 3, 0, 10, 0, 35, 1, 126, 11, 462, 78, 1716, 455, 6435, 2380, 24311, 11628, 92398, 54264, 352947, 245157, 1354102, 1081575, 5215250, 4686826, 20156580, 20030039, 78152535, 84672780, 303906051, 354822776, 1184959314, 1476390160
(list; graph; listen)
|
|
|
OFFSET
|
1,3
|
|
|
COMMENT
|
In general 2^n/m*Sum(r,0,m-1,Cos(2Pi*k*r/m)Cos(2Pi*r/m)^n) is the number of walks of length n between two nodes at distance k in the cycle graph C_m. Here we have m=9 and k=1.
|
|
FORMULA
|
a(n)= 2^n/9*Sum(r, 0, 8, Cos(2Pi*r/9)^(n+1)) G.f.: x(-1+x+2x^2-x^3)/((1+x)(-1+2x)(1-3x^2+x^3)) a(n)=a(n-1)+5a(n-2)-4a(n-3)-5a(n-4)+2a(n-5)
|
|
CROSSREFS
|
Sequence in context: A094472 A028850 A138364 this_sequence A094052 A161678 A081658
Adjacent sequences: A095361 A095362 A095363 this_sequence A095365 A095366 A095367
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Herbert Kociemba (kociemba(AT)t-online.de), Jul 03 2004
|
|
|
Search completed in 0.002 seconds
|
