A027907 - cp's OEIS frontend

A027907 Triangle of trinomial coefficients T(n,k) (n >= 0, 0 <= k <= 2*n), read by rows: n-th row is obtained by expanding (1 + x + x^2)^n.

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	2
6	3
7	2
8	1
9	1
10	3
11	6
12	7
13	6
14	3
15	1
16	1
17	4
18	10
19	16
20	19
21	16
22	10
23	4
24	1
25	1
26	5
27	15
28	30
29	45
30	51
31	45
32	30
33	15
34	5
35	1
36	1
37	6
38	21
39	50
40	90
41	126
42	141
43	126
44	90
45	50
46	21
47	6
48	1
49	1
50	7
51	28
52	77
53	161
54	266
55	357
56	393
57	357
58	266
59	161
60	77
61	28
62	7
63	1
64	1
65	8
66	36
67	112
68	266

[1, 1, 1, 1, 1, 2, 3, 2, 1, 1, 3, 6, 7, 6, 3, 1, 1, 4, 10, 16, 19, 16, 10, 4, 1, 1, 5, 15, 30, 45, 51, 45, 30, 15, 5, 1, 1, 6, 21, 50, 90, 126, 141, 126, 90, 50, 21, 6, 1, 1, 7, 28, 77, 161, 266, 357, 393, 357, 266, 161, 77, 28, 7, 1, 1, 8, 36, 112, 266]

cp's OEIS Frontend

A027907 Triangle of trinomial coefficients T(n,k) (n >= 0, 0 <= k <= 2*n), read by rows: n-th row is obtained by expanding (1 + x + x^2)^n.

Table of values

List of values

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	2
6	3
7	2
8	1
9	1
10	3
11	6
12	7
13	6
14	3
15	1
16	1
17	4
18	10
19	16
20	19
21	16
22	10
23	4
24	1
25	1
26	5
27	15
28	30
29	45
30	51
31	45
32	30
33	15
34	5
35	1
36	1
37	6
38	21
39	50
40	90
41	126
42	141
43	126
44	90
45	50
46	21
47	6
48	1
49	1
50	7
51	28
52	77
53	161
54	266
55	357
56	393
57	357
58	266
59	161
60	77
61	28
62	7
63	1
64	1
65	8
66	36
67	112
68	266

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	2
6	3
7	2
8	1
9	1
10	3
11	6
12	7
13	6
14	3
15	1
16	1
17	4
18	10
19	16
20	19
21	16
22	10
23	4
24	1
25	1
26	5
27	15
28	30
29	45
30	51
31	45
32	30
33	15
34	5
35	1
36	1
37	6
38	21
39	50
40	90
41	126
42	141
43	126
44	90
45	50
46	21
47	6
48	1
49	1
50	7
51	28
52	77
53	161
54	266
55	357
56	393
57	357
58	266
59	161
60	77
61	28
62	7
63	1
64	1
65	8
66	36
67	112
68	266

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	2
6	3
7	2
8	1
9	1
10	3
11	6
12	7
13	6
14	3
15	1
16	1
17	4
18	10
19	16
20	19
21	16
22	10
23	4
24	1
25	1
26	5
27	15
28	30
29	45
30	51
31	45
32	30
33	15
34	5
35	1
36	1
37	6
38	21
39	50
40	90
41	126
42	141
43	126
44	90
45	50
46	21
47	6
48	1
49	1
50	7
51	28
52	77
53	161
54	266
55	357
56	393
57	357
58	266
59	161
60	77
61	28
62	7
63	1
64	1
65	8
66	36
67	112
68	266