A161904 - cp's OEIS frontend

A161904 Array read by rows in which row n list the divisors of n, but if n is a square then the square root of n appears repeated. Also, the divisors appear as pairs (a,b), where a <= b, such that a*b = n.

n	a(n)
1	1
2	1
3	1
4	2
5	1
6	3
7	1
8	4
9	2
10	2
11	1
12	5
13	1
14	6
15	2
16	3
17	1
18	7
19	1
20	8
21	2
22	4
23	1
24	9
25	3
26	3
27	1
28	10
29	2
30	5
31	1
32	11
33	1
34	12
35	2
36	6
37	3
38	4
39	1
40	13
41	1
42	14
43	2
44	7
45	1
46	15
47	3
48	5
49	1
50	16
51	2
52	8
53	4
54	4
55	1
56	17
57	1
58	18
59	2
60	9
61	3
62	6
63	1
64	19
65	1
66	20
67	2
68	10
69	4
70	5
71	1
72	21
73	3
74	7

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

cp's OEIS Frontend

A161904 Array read by rows in which row n list the divisors of n, but if n is a square then the square root of n appears repeated. Also, the divisors appear as pairs (a,b), where a <= b, such that a*b = n.

Table of values

List of values

n	a(n)
1	1
2	1
3	1
4	2
5	1
6	3
7	1
8	4
9	2
10	2
11	1
12	5
13	1
14	6
15	2
16	3
17	1
18	7
19	1
20	8
21	2
22	4
23	1
24	9
25	3
26	3
27	1
28	10
29	2
30	5
31	1
32	11
33	1
34	12
35	2
36	6
37	3
38	4
39	1
40	13
41	1
42	14
43	2
44	7
45	1
46	15
47	3
48	5
49	1
50	16
51	2
52	8
53	4
54	4
55	1
56	17
57	1
58	18
59	2
60	9
61	3
62	6
63	1
64	19
65	1
66	20
67	2
68	10
69	4
70	5
71	1
72	21
73	3
74	7

n	a(n)
1	1
2	1
3	1
4	2
5	1
6	3
7	1
8	4
9	2
10	2
11	1
12	5
13	1
14	6
15	2
16	3
17	1
18	7
19	1
20	8
21	2
22	4
23	1
24	9
25	3
26	3
27	1
28	10
29	2
30	5
31	1
32	11
33	1
34	12
35	2
36	6
37	3
38	4
39	1
40	13
41	1
42	14
43	2
44	7
45	1
46	15
47	3
48	5
49	1
50	16
51	2
52	8
53	4
54	4
55	1
56	17
57	1
58	18
59	2
60	9
61	3
62	6
63	1
64	19
65	1
66	20
67	2
68	10
69	4
70	5
71	1
72	21
73	3
74	7

n	a(n)
1	1
2	1
3	1
4	2
5	1
6	3
7	1
8	4
9	2
10	2
11	1
12	5
13	1
14	6
15	2
16	3
17	1
18	7
19	1
20	8
21	2
22	4
23	1
24	9
25	3
26	3
27	1
28	10
29	2
30	5
31	1
32	11
33	1
34	12
35	2
36	6
37	3
38	4
39	1
40	13
41	1
42	14
43	2
44	7
45	1
46	15
47	3
48	5
49	1
50	16
51	2
52	8
53	4
54	4
55	1
56	17
57	1
58	18
59	2
60	9
61	3
62	6
63	1
64	19
65	1
66	20
67	2
68	10
69	4
70	5
71	1
72	21
73	3
74	7