OFFSET
0,5
COMMENTS
Diagonal sums of the Pascal-(1,3,1) triangle A081578.
LINKS
R. J. Mathar, Tilings of rectangular regions by rectangular tiles: Counts derived from transfer matrices, arXiv:1406.7788 [math.CO], 2014.
Index entries for linear recurrences with constant coefficients, signature (1,1,3).
FORMULA
G.f.: 1/(1-x-x^2-3x^3).
MATHEMATICA
LinearRecurrence[{1, 1, 3}, {0, 0, 1}, 50] (* Vladimir Joseph Stephan Orlovsky, May 25 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Jan 24 2005
EXTENSIONS
Name clarified by Michel Marcus, Aug 07 2022
STATUS
approved