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,-5,1,2,-1).
FORMULA
a(n) = 4*a(n-1) - 5*a(n-2) + a(n-3) + 2*a(n-4) - a(n-5).
G.f.: f(x)/g(x), where f(x) = x*(1 + 3*x) and g(x) = (1 - x - x^2)(1 - x)^3.
a(n) = 2*Fibonacci(n+6) + Lucas(n+4) - n*(2*n + 11) - 23. - Ehren Metcalfe, Jul 08 2019
MATHEMATICA
(See A213768.)
PROG
(Magma) [2*Fibonacci(n+6)+Lucas(n+4)-n*(2*n+11)-23: n in [1..35]]; // Vincenzo Librandi, Jul 09 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 21 2012
STATUS
approved