A340531 - cp's OEIS frontend

A340531 Irregular triangle read by rows T(n,k), (n >= 1, k >= 1), in which row n has length is A000070(n-1) and every column k is A024916, the sum of all divisors of all numbers <= n.

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

[1, 4, 1, 8, 4, 1, 1, 15, 8, 4, 4, 1, 1, 1, 21, 15, 8, 8, 4, 4, 4, 1, 1, 1, 1, 1, 33, 21, 15, 15, 8, 8, 8, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 41, 33, 21, 21, 15, 15, 15, 8, 8, 8, 8, 8, 4, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 56, 41, 33, 33, 21, 21, 21, 15, 15, 15, 15, 15]

cp's OEIS Frontend

A340531 Irregular triangle read by rows T(n,k), (n >= 1, k >= 1), in which row n has length is A000070(n-1) and every column k is A024916, the sum of all divisors of all numbers <= n.

Table of values

List of values

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

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

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