A162306 - cp's OEIS frontend

A162306 Irregular triangle in which row n contains the numbers <= n whose prime factors are a subset of prime factors of n.

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

[1, 1, 2, 1, 3, 1, 2, 4, 1, 5, 1, 2, 3, 4, 6, 1, 7, 1, 2, 4, 8, 1, 3, 9, 1, 2, 4, 5, 8, 10, 1, 11, 1, 2, 3, 4, 6, 8, 9, 12, 1, 13, 1, 2, 4, 7, 8, 14, 1, 3, 5, 9, 15, 1, 2, 4, 8, 16, 1, 17, 1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 1, 19, 1, 2, 4, 5, 8, 10, 16, 20, 1, 3, 7, 9, 21, 1, 2, 4, 8, 11, 16, 22, 1, 23]

cp's OEIS Frontend

A162306 Irregular triangle in which row n contains the numbers <= n whose prime factors are a subset of prime factors of n.

Table of values

List of values

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

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

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