A366723 - cp's OEIS frontend

A366723 a(n) = Sum_{k=1..n} (-1)^(k-1) * binomial(floor(n/k)+4,5).

n	a(n)
1	1
2	5
3	21
4	50
5	121
6	236
7	447
8	736
9	1247
10	1896
11	2898
12	4151
13	5972
14	8146
15	11292
16	14797
17	19643
18	25248
19	32564
20	40663
21	51515
22	63168
23	78119
24	94452
25	114998
26	136933
27	164849
28	193753
29	229714
30	268334
31	314711
32	362824
33	422746
34	483950
35	558046
36	635070
37	726461
38	820420
39	934186
40	1048245

[1, 5, 21, 50, 121, 236, 447, 736, 1247, 1896, 2898, 4151, 5972, 8146, 11292, 14797, 19643, 25248, 32564, 40663, 51515, 63168, 78119, 94452, 114998, 136933, 164849, 193753, 229714, 268334, 314711, 362824, 422746, 483950, 558046, 635070, 726461, 820420, 934186, 1048245]

cp's OEIS Frontend

A366723 a(n) = Sum_{k=1..n} (-1)^(k-1) * binomial(floor(n/k)+4,5).

Table of values

List of values