|
| |
|
|
A051929
|
|
Number of independent sets of vertices in graph K_4 X C_n (n > 2).
|
|
2
|
|
|
|
5, 1, 21, 73, 325, 1361, 5781, 24473, 103685, 439201, 1860501, 7881193, 33385285, 141422321, 599074581, 2537720633, 10749957125, 45537549121, 192900153621, 817138163593, 3461452808005, 14662949395601, 62113250390421, 263115950957273, 1114577054219525
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,1
|
|
|
LINKS
|
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,5,1).
|
|
|
FORMULA
|
a(n) = 3*a(n-1) + 5*a(n-2) + a(n-3).
From Colin Barker, May 22 2012: (Start)
a(n) = (3*(-1)^n+(2-sqrt(5))^n+(2+sqrt(5))^n).
G.f.: (5 - 14*x - 7*x^2) / ((1 + x)*(1 - 4*x - x^2)).
(End)
|
|
|
PROG
|
(PARI) Vec((5 - 14*x - 7*x^2) / ((1 + x)*(1 - 4*x - x^2)) + O(x^30)) \\ Colin Barker, May 11 2017
|
|
|
CROSSREFS
|
Row 4 of A287376.
Sequence in context: A029757 A146056 A101625 * A347487 A213118 A259682
Adjacent sequences: A051926 A051927 A051928 * A051930 A051931 A051932
|
|
|
KEYWORD
|
easy,nonn
|
|
|
AUTHOR
|
Stephen G. Penrice (spenrice(AT)ets.org), Dec 19 1999
|
|
|
EXTENSIONS
|
More terms from James A. Sellers, Dec 20 1999
|
|
|
STATUS
|
approved
|
| |
|
|
