|
| |
|
|
A001170
|
|
Number of board-pair-pile polyominoes with n cells.
(Formerly M1638 N0640)
|
|
3
| |
|
|
1, 2, 6, 19, 63, 216, 760, 2723, 9880, 36168, 133237, 492993, 1829670, 6804267, 25336611, 94416842, 351989967, 1312471879, 4894023222, 18248301701, 68036380665, 253638655582, 945464013411, 3523978989671, 13133649924269
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
REFERENCES
| W. F. Lunnon, Counting polyominoes, pp. 347-372 of A. O. L. Atkin and B. J. Birch, editors, Computers in Number Theory. Academic Press, NY, 1971.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
|
LINKS
| Moa Apagodu, Counting hexagonal lattice animals.
D. Zeilberger, The umbral transfer-matrix method. III. Counting animals
|
|
|
CROSSREFS
| Sequence in context: A006724 A057409 A141771 * A001168 A193111 A119255
Adjacent sequences: A001167 A001168 A001169 * A001171 A001172 A001173
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
| |
|
|
