A013938 - cp's OEIS frontend

A013938 a(n) = Sum_{k=1..n} floor(n/k^4).

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

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

cp's OEIS Frontend

A013938 a(n) = Sum_{k=1..n} floor(n/k^4).

Table of values

List of values

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

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

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