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A259332
Triangle read by rows: T(n,k) = number of column-convex polyominoes with perimeter n and k columns (1 <= k <= n).
1
1, 1, 2, 1, 6, 5, 1, 12, 27, 14, 1, 20, 85, 112, 42, 1, 30, 205, 492, 450, 132, 1, 42, 420, 1582, 2565, 1782, 429, 1, 56, 770, 4172, 10415, 12562, 7007, 1430
OFFSET
1,3
LINKS
M.-P. Delest, Utilisation des Langages Algébriques et du Calcul Formel Pour le Codage et l'Enumeration des Polyominos, Ph.D. Dissertation, Université Bordeaux I, May 1987. [Scanned copy, with permission. A very large file.] See Figure 8.
M.-P. Delest, Utilisation des Langages Algébriques et du Calcul Formel Pour le Codage et l'Enumeration des Polyominos, Ph.D. Dissertation, Université Bordeaux I, May 1987. (Annotated scanned copy of a small part of the thesis)
M.-P. Delest, Generating functions for column-convex polyominoes, J. Combin. Theory Ser. A 48 (1988), no. 1, 12-31.
S. Dulucq, Etude combinatoire de problèmes d'énumeration, d'algorithmique sur les arbres et de codage par des mots, a thesis presented to L'Université De Bordeaux I, 1987. (Annotated scanned copy)
EXAMPLE
Triangle begins:
1,
1,2,
1,6,5,
1,12,27,14,
1,20,85,112,42,
1,30,205,492,450,132,
1,42,420,1582,2565,1782,429,
1,56,770,4172,10415,12562,7007,1430,
...
CROSSREFS
Row sums are A006026.
Sequence in context: A205455 A338135 A350510 * A108767 A046817 A193817
KEYWORD
nonn,tabl,more
AUTHOR
N. J. A. Sloane, Jun 24 2015
STATUS
approved