

A291085


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


0



1, 1, 4, 4, 2, 1, 20, 19, 13, 8, 3, 1, 104, 98, 76, 52, 28, 13, 4, 1, 556, 526, 434, 319, 201, 111, 50, 19, 5, 1, 3032, 2887, 2470, 1910, 1316, 811, 436, 205, 80, 26, 6, 1, 16778, 16073, 14085, 11304, 8259, 5489, 3284, 1763, 833, 344, 119, 34, 7, 1, 93872, 90386, 80584, 66514, 50680, 35588, 22912, 13476, 7176, 3437, 1456, 539, 168, 43, 8, 1
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OFFSET

0,3


LINKS

Table of n, a(n) for n=0..71.
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:
1,1,
4,4,2,1,
20,19,13,8,3,1,
104,98,76,52,28,13,4,1,
556,526,434,319,201,111,50,19,5,1,
3032,2887,2470,1910,1316,811,436,205,80,26,6,1,
16778,16073,14085,11304,8259,5489,3284,1763,833,344,119,34,7,1,
93872,90386,80584,66514,50680,35588,22912,13476,7176,3437,1456,539,168,43,8,1,
...


CROSSREFS

First column is A291089.
Sequence in context: A168455 A300153 A182781 * A193556 A120438 A192977
Adjacent sequences: A291082 A291083 A291084 * A291086 A291087 A291088


KEYWORD

nonn,tabf


AUTHOR

N. J. A. Sloane, Aug 19 2017


STATUS

approved



