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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). 0
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 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..36.

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'Universite 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: A066654 A145960 A205455 * A108767 A046817 A193817

Adjacent sequences:  A259329 A259330 A259331 * A259333 A259334 A259335

KEYWORD

nonn,tabl,more

AUTHOR

N. J. A. Sloane, Jun 24 2015

STATUS

approved

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Last modified December 16 09:06 EST 2019. Contains 330020 sequences. (Running on oeis4.)