A003989 - cp's OEIS frontend

A003989 Triangle T from the array A(x, y) = gcd(x,y), for x >= 1, y >= 1, read by antidiagonals.

n	a(n)
1	1
2	1
3	1
4	1
5	2
6	1
7	1
8	1
9	1
10	1
11	1
12	2
13	3
14	2
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	2
24	1
25	4
26	1
27	2
28	1
29	1
30	1
31	3
32	1
33	1
34	3
35	1
36	1
37	1
38	2
39	1
40	2
41	5
42	2
43	1
44	2
45	1
46	1
47	1
48	1
49	1
50	1
51	1
52	1
53	1
54	1
55	1
56	1
57	2
58	3
59	4
60	1
61	6
62	1
63	4
64	3
65	2
66	1
67	1
68	1
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	1
78	1
79	1
80	2
81	1
82	2
83	1
84	2
85	7
86	2
87	1
88	2
89	1
90	2
91	1
92	1
93	1
94	3
95	1
96	5
97	3
98	1
99	1
100	3
101	5
102	1
103	3
104	1
105	1
106	1
107	2
108	1

[1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 2, 1, 1, 1, 3, 1, 1, 3, 1, 1, 1, 2, 1, 2, 5, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 1, 6, 1, 4, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 7, 2, 1, 2, 1, 2, 1, 1, 1, 3, 1, 5, 3, 1, 1, 3, 5, 1, 3, 1, 1, 1, 2, 1]

cp's OEIS Frontend

A003989 Triangle T from the array A(x, y) = gcd(x,y), for x >= 1, y >= 1, read by antidiagonals.

Table of values

List of values

n	a(n)
1	1
2	1
3	1
4	1
5	2
6	1
7	1
8	1
9	1
10	1
11	1
12	2
13	3
14	2
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	2
24	1
25	4
26	1
27	2
28	1
29	1
30	1
31	3
32	1
33	1
34	3
35	1
36	1
37	1
38	2
39	1
40	2
41	5
42	2
43	1
44	2
45	1
46	1
47	1
48	1
49	1
50	1
51	1
52	1
53	1
54	1
55	1
56	1
57	2
58	3
59	4
60	1
61	6
62	1
63	4
64	3
65	2
66	1
67	1
68	1
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	1
78	1
79	1
80	2
81	1
82	2
83	1
84	2
85	7
86	2
87	1
88	2
89	1
90	2
91	1
92	1
93	1
94	3
95	1
96	5
97	3
98	1
99	1
100	3
101	5
102	1
103	3
104	1
105	1
106	1
107	2
108	1

n	a(n)
1	1
2	1
3	1
4	1
5	2
6	1
7	1
8	1
9	1
10	1
11	1
12	2
13	3
14	2
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	2
24	1
25	4
26	1
27	2
28	1
29	1
30	1
31	3
32	1
33	1
34	3
35	1
36	1
37	1
38	2
39	1
40	2
41	5
42	2
43	1
44	2
45	1
46	1
47	1
48	1
49	1
50	1
51	1
52	1
53	1
54	1
55	1
56	1
57	2
58	3
59	4
60	1
61	6
62	1
63	4
64	3
65	2
66	1
67	1
68	1
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	1
78	1
79	1
80	2
81	1
82	2
83	1
84	2
85	7
86	2
87	1
88	2
89	1
90	2
91	1
92	1
93	1
94	3
95	1
96	5
97	3
98	1
99	1
100	3
101	5
102	1
103	3
104	1
105	1
106	1
107	2
108	1

n	a(n)
1	1
2	1
3	1
4	1
5	2
6	1
7	1
8	1
9	1
10	1
11	1
12	2
13	3
14	2
15	1
16	1
17	1
18	1
19	1
20	1
21	1
22	1
23	2
24	1
25	4
26	1
27	2
28	1
29	1
30	1
31	3
32	1
33	1
34	3
35	1
36	1
37	1
38	2
39	1
40	2
41	5
42	2
43	1
44	2
45	1
46	1
47	1
48	1
49	1
50	1
51	1
52	1
53	1
54	1
55	1
56	1
57	2
58	3
59	4
60	1
61	6
62	1
63	4
64	3
65	2
66	1
67	1
68	1
69	1
70	1
71	1
72	1
73	1
74	1
75	1
76	1
77	1
78	1
79	1
80	2
81	1
82	2
83	1
84	2
85	7
86	2
87	1
88	2
89	1
90	2
91	1
92	1
93	1
94	3
95	1
96	5
97	3
98	1
99	1
100	3
101	5
102	1
103	3
104	1
105	1
106	1
107	2
108	1