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A181989
Number of independent sets of nodes in graph C_5 x P_n (n >= 0).
2
1, 11, 81, 621, 4741, 36211, 276561, 2112241, 16132281, 123210611, 941023441, 7187084861, 54891500621, 419234905211, 3201914754721, 24454686308481, 186773143027761, 1426483517982011, 10894795654704401, 83209214029813101, 635511992964231701, 4853735225243983011
OFFSET
0,2
LINKS
C. Bautista-Ramos and C. Guillen-Galvan, Fibonacci numbers of generalized Zykov sums, J. Integer Seq., 15 (2012), Article 12.7.8.
FORMULA
a(n) = 7*a(n-1) + 5*a(n-2) - a(n-3) with a(0)=1, a(1)=11, a(2)=81.
G.f.: (1+4*x-x^2)/(x^3-5*x^2-7*x+1).
CROSSREFS
Row 5 of A286513.
Sequence in context: A333061 A055429 A227556 * A199557 A003730 A334340
KEYWORD
nonn,easy
AUTHOR
Cesar Bautista, Apr 04 2012
STATUS
approved