A380408 - cp's OEIS frontend

A380408 a(n) = Sum_{k>=0} floor(n/(2k)!).

n	a(n)
0	0
1	1
2	3
3	4
4	6
5	7
6	9
7	10
8	12
9	13
10	15
11	16
12	18
13	19
14	21
15	22
16	24
17	25
18	27
19	28
20	30
21	31
22	33
23	34
24	37
25	38
26	40
27	41
28	43
29	44
30	46
31	47
32	49
33	50
34	52
35	53
36	55
37	56
38	58
39	59
40	61
41	62
42	64
43	65
44	67
45	68
46	70
47	71
48	74
49	75
50	77
51	78
52	80
53	81
54	83
55	84
56	86
57	87
58	89
59	90
60	92
61	93
62	95
63	96
64	98
65	99
66	101
67	102
68	104
69	105
70	107

[0, 1, 3, 4, 6, 7, 9, 10, 12, 13, 15, 16, 18, 19, 21, 22, 24, 25, 27, 28, 30, 31, 33, 34, 37, 38, 40, 41, 43, 44, 46, 47, 49, 50, 52, 53, 55, 56, 58, 59, 61, 62, 64, 65, 67, 68, 70, 71, 74, 75, 77, 78, 80, 81, 83, 84, 86, 87, 89, 90, 92, 93, 95, 96, 98, 99, 101, 102, 104, 105, 107]

cp's OEIS Frontend

A380408 a(n) = Sum_{k>=0} floor(n/(2k)!).

Table of values

List of values

n	a(n)
0	0
1	1
2	3
3	4
4	6
5	7
6	9
7	10
8	12
9	13
10	15
11	16
12	18
13	19
14	21
15	22
16	24
17	25
18	27
19	28
20	30
21	31
22	33
23	34
24	37
25	38
26	40
27	41
28	43
29	44
30	46
31	47
32	49
33	50
34	52
35	53
36	55
37	56
38	58
39	59
40	61
41	62
42	64
43	65
44	67
45	68
46	70
47	71
48	74
49	75
50	77
51	78
52	80
53	81
54	83
55	84
56	86
57	87
58	89
59	90
60	92
61	93
62	95
63	96
64	98
65	99
66	101
67	102
68	104
69	105
70	107

n	a(n)
0	0
1	1
2	3
3	4
4	6
5	7
6	9
7	10
8	12
9	13
10	15
11	16
12	18
13	19
14	21
15	22
16	24
17	25
18	27
19	28
20	30
21	31
22	33
23	34
24	37
25	38
26	40
27	41
28	43
29	44
30	46
31	47
32	49
33	50
34	52
35	53
36	55
37	56
38	58
39	59
40	61
41	62
42	64
43	65
44	67
45	68
46	70
47	71
48	74
49	75
50	77
51	78
52	80
53	81
54	83
55	84
56	86
57	87
58	89
59	90
60	92
61	93
62	95
63	96
64	98
65	99
66	101
67	102
68	104
69	105
70	107

n	a(n)
0	0
1	1
2	3
3	4
4	6
5	7
6	9
7	10
8	12
9	13
10	15
11	16
12	18
13	19
14	21
15	22
16	24
17	25
18	27
19	28
20	30
21	31
22	33
23	34
24	37
25	38
26	40
27	41
28	43
29	44
30	46
31	47
32	49
33	50
34	52
35	53
36	55
37	56
38	58
39	59
40	61
41	62
42	64
43	65
44	67
45	68
46	70
47	71
48	74
49	75
50	77
51	78
52	80
53	81
54	83
55	84
56	86
57	87
58	89
59	90
60	92
61	93
62	95
63	96
64	98
65	99
66	101
67	102
68	104
69	105
70	107