A216622 - cp's OEIS frontend

A216622 Square array read by antidiagonals: T(n,k) = Sum_{c|n, d|k} phi(lcm(c,d)) for n >= 1, k >= 1.

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

[1, 2, 2, 3, 4, 3, 4, 6, 6, 4, 5, 8, 7, 8, 5, 6, 10, 12, 12, 10, 6, 7, 12, 15, 14, 15, 12, 7, 8, 14, 14, 20, 20, 14, 14, 8, 9, 16, 21, 24, 13, 24, 21, 16, 9, 10, 18, 24, 28, 30, 30, 28, 24, 18, 10, 11, 20, 19, 26, 35, 28, 35, 26, 19, 20, 11, 12, 22, 30, 36, 40]

cp's OEIS Frontend

A216622 Square array read by antidiagonals: T(n,k) = Sum_{c|n, d|k} phi(lcm(c,d)) for n >= 1, k >= 1.

Table of values

List of values

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

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

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