A350221 - cp's OEIS frontend

A350221 a(n) = Sum_{k=1..n} (-1)^(k+1) * floor((n/k)^2).

n	a(n)
1	1
2	3
3	8
4	12
5	21
6	29
7	40
8	52
9	67
10	83
11	100
12	116
13	140
14	160
15	185
16	210
17	237
18	264
19	298
20	327
21	363
22	397
23	435
24	472
25	514
26	557
27	602
28	644
29	690
30	741
31	791
32	837
33	897
34	950
35	1009
36	1063
37	1126
38	1185
39	1253
40	1313
41	1381
42	1450
43	1521
44	1593
45	1667
46	1739
47	1820
48	1894
49	1973
50	2054
51	2140

[1, 3, 8, 12, 21, 29, 40, 52, 67, 83, 100, 116, 140, 160, 185, 210, 237, 264, 298, 327, 363, 397, 435, 472, 514, 557, 602, 644, 690, 741, 791, 837, 897, 950, 1009, 1063, 1126, 1185, 1253, 1313, 1381, 1450, 1521, 1593, 1667, 1739, 1820, 1894, 1973, 2054, 2140]

cp's OEIS Frontend

A350221 a(n) = Sum_{k=1..n} (-1)^(k+1) * floor((n/k)^2).

Table of values

List of values