OFFSET
3,1
LINKS
Matthias Koch and Sascha Kurz, Enumeration of generalized polyominoes, preprint, arXiv:math.CO/0605144
EXAMPLE
a(3)=160 because there are 160 polyiamonds consisting of 9 triangles and a(4)=1285 because there are 1285 polyominoes consisting of 9 squares.
CROSSREFS
KEYWORD
nonn
AUTHOR
Sascha Kurz, Jun 09 2006
STATUS
approved