OFFSET
1,2
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (4,-4,-2,4,0,-1).
FORMULA
a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6).
G.f.: f(x)/g(x), where f(x) = x*(1 + 4*x - 2*x^2 - 7*x^3) and g(x) = (1 - 2*x + x^3 )^2.
MATHEMATICA
(See A213768.)
LinearRecurrence[{4, -4, -2, 4, 0, -1}, {1, 8, 26, 63, 136, 272}, 40] (* Harvey P. Dale, Jan 08 2015 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 21 2012
STATUS
approved