A291087 - OEIS

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A291087

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

0

1, 1, 2, 3, 2, 1, 7, 11, 10, 7, 3, 1, 28, 46, 48, 39, 24, 12, 4, 1, 122, 207, 233, 208, 151, 92, 45, 18, 5, 1, 562, 977, 1154, 1099, 880, 606, 356, 179, 74, 25, 6, 1, 2693, 4769, 5826, 5815, 4975, 3726, 2451, 1419, 714, 310, 112, 33, 7, 1, 13288, 23872, 29904, 30926, 27768, 22112, 15736, 10039, 5720, 2898, 1288, 496, 160, 42, 8, 1

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

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,

2,3,2,1,

7,11,10,7,3,1,

28,46,48,39,24,12,4,1,

122,207,233,208,151,92,45,18,5,1,

562,977,1154,1099,880,606,356,179,74,25,6,1,

2693,4769,5826,5815,4975,3726,2451,1419,714,310,112,33,7,1,

...

CROSSREFS

The first two columns are A291091 and A291090.

Sequence in context: A358605 A360026 A062323 * A020858 A090664 A086764

Adjacent sequences: A291084 A291085 A291086 * A291088 A291089 A291090

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, Aug 19 2017

STATUS

approved