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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A182880 Triangle read by rows: T(n,k) is the number of weighted lattice paths in L_n having k (1,1)-steps. L_n is the set of lattice paths of weight n that start at (0,0) and end on the horizontal axis and whose steps are of the following four kinds: a (1,0)-step with weight 1; a (1,0)-step with weight 2; a (1,1)-step with weight 2; a (1,-1)-step with weight 1. The weight of a path is the sum of the weights of its steps.

Table of values

n a(n)
0 1
1 1
2 2
3 3
4 2
5 5
6 6
7 8
8 18
9 13
10 44
11 6
12 21
13 102
14 30
15 34
16 222
17 120
18 55
19 466
20 390
21 20
22 89
23 948
24 1140
25 140
26 144
27 1884
28 3066
29 700
30 233
31 3672
32 7770
33 2800
34 70
35 377
36 7044
37 18780
38 9800
39 630
40 610
41 13332
42 43710
43 31080
44 3780
45 987
46 24946
47 98610
48 91560
49 17850
50 252
51 1597
52 46218
53 216732
54 254400
55 72450
56 2772

List of values

[1, 1, 2, 3, 2, 5, 6, 8, 18, 13, 44, 6, 21, 102, 30, 34, 222, 120, 55, 466, 390, 20, 89, 948, 1140, 140, 144, 1884, 3066, 700, 233, 3672, 7770, 2800, 70, 377, 7044, 18780, 9800, 630, 610, 13332, 43710, 31080, 3780, 987, 24946, 98610, 91560, 17850, 252, 1597, 46218, 216732, 254400, 72450, 2772]

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