A143544 - cp's OEIS frontend

A143544 Triangle read by rows, T(n,k) = 2 if n is prime, 1 otherwise; 1<=k<=n.

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

[1, 2, 2, 2, 2, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2]

cp's OEIS Frontend

A143544 Triangle read by rows, T(n,k) = 2 if n is prime, 1 otherwise; 1<=k<=n.

Table of values

List of values

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

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

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