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A059684 revision #13

A059684
Triangle T(n,k) giving number of 4 X k polyominoes with n cells (n >= 4, 1<=k<=n-3).
2
1, 0, 3, 0, 6, 15, 0, 2, 39, 30, 0, 1, 59, 148, 61, 0, 0, 42, 349, 383, 97, 0, 0, 21, 518, 1304, 822, 155
OFFSET
4,3
LINKS
R. C. Read, Contributions to the cell growth problem, Canad. J. Math., 14 (1962), 1-20.
EXAMPLE
Triangle starts:
1;
0,3;
0,6,15;
0,2,39,30;
...
There are T(5,2)=3 out of 12 pentominoes that fill the 4X2 shape: the L, N and Y. The F, T, V, W, X, and Z require both dimensions >= 3; the P and U would fit but not touch all sides; the I requires one dimension of 5. - R. J. Mathar, May 08 2019
CROSSREFS
Sequence in context: A057381 A144091 A019145 * * A270509 A083350
KEYWORD
nonn,easy,nice,tabl,more,changed
AUTHOR
N. J. A. Sloane, Feb 05 2001
STATUS
approved