A291080 - OEIS

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A291080

Irregular triangle read by rows: T(n,m) = number of lattice paths of type {A^H}_R terminating at point (n, m).

1, 3, 2, 1, 19, 16, 10, 4, 1, 141, 126, 90, 50, 21, 6, 1, 1107, 1016, 784, 504, 266, 112, 36, 8, 1, 8953, 8350, 6765, 4740, 2850, 1452, 615, 210, 55, 10, 1, 73789, 69576, 58278, 43252, 28314, 16236, 8074, 3432, 1221, 352, 78, 12, 1, 616227, 585690, 502593, 388752, 270270, 168168, 93093, 45474, 19383, 7098, 2184, 546, 105, 14, 1

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..63.

Rezig Boualam and Moussa Ahmia, Log-concavity and strong q-log-convexity for some generalized triangular arrays, arXiv:2409.18886 [math.CO], 2024. See pp. 3,6.

Veronika Irvine, Lace Tessellations: A mathematical model for bobbin lace and an exhaustive combinatorial search for patterns, PhD Dissertation, University of Victoria, 2016.

EXAMPLE

Triangle begins:

3,2,1;

19,16,10,4,1;

141,126,90,50,21,6,1;