OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
G. Kilibarda and V. Jovovic, Enumeration of some classes of T_0-hypergraphs, arXiv:1411.4187 [math.CO], 2014.
Index entries for linear recurrences with constant coefficients, signature (17,-92,160).
FORMULA
a(n) = 8^n - 3*5^n + 2*4^n.
From Colin Barker, Jul 13 2013: (Start)
a(n) = 17*a(n-1) - 92*a(n-2) + 160*a(n-3).
G.f.: x*(4*x+1) / ((1-4*x)*(1-5*x)*(1-8*x)). (End)
MATHEMATICA
CoefficientList[Series[-x*(4*x + 1)/((4*x - 1)*(5*x - 1)*(8*x - 1)), {x, 0, 50}], x] (* G. C. Greubel, Oct 05 2017 *)
PROG
(PARI) x='x+O('x^50); Vec(x*(4*x+1)/((1-4*x)*(1-5*x)*(1-8*x))) \\ G. C. Greubel, Oct 05 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Goran Kilibarda, Vladeta Jovovic, Apr 15 2004
EXTENSIONS
Additional term from Colin Barker, Jul 13 2013
STATUS
approved