A243211 - cp's OEIS frontend

A243211 Triangle T(n, k) = Numbers of ways to place k points on a triangular grid of side n so that no three of them are vertices of an equilateral triangle with sides parallel to the grid. Triangle read by rows.

n	a(n)
1	1
2	1
3	1
4	3
5	3
6	1
7	6
8	15
9	15
10	3
11	1
12	10
13	45
14	107
15	128
16	63
17	10
18	1
19	15
20	105
21	428
22	1062
23	1566
24	1276
25	507
26	69
27	1
28	21
29	210
30	1282
31	5160
32	13971
33	25191
34	29235
35	20508
36	7747
37	1251
38	42
39	1
40	1
41	28
42	378
43	3198
44	18591
45	77124
46	231090
47	498097
48	759117
49	792942
50	540361
51	222597
52	49053

[1, 1, 1, 3, 3, 1, 6, 15, 15, 3, 1, 10, 45, 107, 128, 63, 10, 1, 15, 105, 428, 1062, 1566, 1276, 507, 69, 1, 21, 210, 1282, 5160, 13971, 25191, 29235, 20508, 7747, 1251, 42, 1, 1, 28, 378, 3198, 18591, 77124, 231090, 498097, 759117, 792942, 540361, 222597, 49053]

cp's OEIS Frontend

A243211 Triangle T(n, k) = Numbers of ways to place k points on a triangular grid of side n so that no three of them are vertices of an equilateral triangle with sides parallel to the grid. Triangle read by rows.

Table of values

List of values