A110663 - cp's OEIS frontend

A110663 Triangle read by rows: T(n,k) = Sum_{j=k..n} phi(j) (1<=k<=n), where phi is Euler's totient function.

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

[1, 2, 1, 4, 3, 2, 6, 5, 4, 2, 10, 9, 8, 6, 4, 12, 11, 10, 8, 6, 2, 18, 17, 16, 14, 12, 8, 6, 22, 21, 20, 18, 16, 12, 10, 4, 28, 27, 26, 24, 22, 18, 16, 10, 6, 32, 31, 30, 28, 26, 22, 20, 14, 10, 4, 42, 41, 40, 38, 36, 32, 30, 24, 20, 14, 10, 46, 45, 44, 42, 40, 36, 34, 28, 24, 18, 14, 4]

cp's OEIS Frontend

A110663 Triangle read by rows: T(n,k) = Sum_{j=k..n} phi(j) (1<=k<=n), where phi is Euler's totient function.

Table of values

List of values

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

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

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