OFFSET
0,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..960
Tomislav Došlić and Frode Måløy, Chain hexagonal cacti: Matchings and independent sets, Discr. Math., 310 (2010), 1676-1690.
Index entries for linear recurrences with constant coefficients, signature (12,-11).
FORMULA
From Felix P. Muga II, Mar 19 2014: (Start)
a(n) = 12*a(n-1)-11*a(n-2) for n>=2, a(0)=2, a(1)=18.
a(n) = a(n-1)+16*11^(n-1) for n >=1, a(0)=2.
a(n) = 10*a(n-1)+11*a(n-2)-8 for n>=2, a(0)=2, a(1)=18.
a(n) = (8/5)*11^n + 2/5. (End)
MATHEMATICA
CoefficientList[Series[(2-6x)/(1-12x+11x^2), {x, 0, 40}], x] (* or *) LinearRecurrence[{12, -11}, {2, 18}, 40] (* Harvey P. Dale, Jan 27 2022 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 22 2010
STATUS
approved