OFFSET
0,2
REFERENCES
J. P. McSorley, Counting structures in the Moebius ladder, Discrete Math., 184 (1998), 137-164.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (8,-26,44,-41,20,-4).
FORMULA
a(n) = 10*n*2^n-n^3-5*n^2-11*n.
G.f.: -x*(8*x^4-20*x^3+27*x^2-6*x-3) / ((x-1)^4*(2*x-1)^2). - Colin Barker, Apr 05 2013
MATHEMATICA
CoefficientList[Series[- x (8 x^4 - 20 x^3 + 27 x^2 - 6 x - 3)/((x - 1)^4 (2*x - 1)^2), {x, 0, 30}], x] (* Vincenzo Librandi, Oct 16 2013 *)
LinearRecurrence[{8, -26, 44, -41, 20, -4}, {0, 3, 30, 135, 452, 1295}, 30] (* Harvey P. Dale, Apr 05 2018 *)
PROG
(Magma) [10*n*2^n-n^3-5*n^2-11*n: n in [0..30]]; // Vincenzo Librandi, Oct 16 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved