OFFSET
0,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
R. J. Mathar, Tiling nXm rectangles with 1X1 and sXs squares arXiv:1609.03964 [math.CO] (2016) Section 4.1.
Index entries for linear recurrences with constant coefficients, signature (2,16,1,-27,1,4).
FORMULA
G.f.: ( -1+x+5*x^2-x^4 ) / ( -1+2*x+16*x^2+x^3-27*x^4+x^5+4*x^6 ).
a(n) = 2a(n-1) + 16a(n-2) + a(n-3) - 27a(n-4) + a(n-5) + 4a(n-6) - Keith Schneider (kschneid(AT)bulldog.unca.edu), Apr 02 2006
MATHEMATICA
LinearRecurrence[{2, 16, 1, -27, 1, 4}, {1, 1, 13, 43, 269, 1213}, 22] (* Jean-François Alcover, Oct 30 2018 *)
CoefficientList[Series[(-1+x+5*x^2-x^4)/(-1+2*x+16*x^2+x^3-27*x^4+x^5+4*x^6), {x, 0, 50}], x] (* Stefano Spezia, Oct 30 2018 *)
PROG
(Magma) I:=[1, 1, 13, 43, 269, 1213]; [n le 6 select I[n] else 2*Self(n-1)+16*Self(n-2)+Self(n-3)-27*Self(n-4)+Self(n-5)+4*Self(n-6): n in [1..30]]; // Vincenzo Librandi, Oct 30 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Reiner Martin, Jul 23 2001
STATUS
approved