A128223 - cp's OEIS frontend

A128223 a(n) = if n mod 2 = 0 then n*(n+1)/2 otherwise (n+1)^2/2-1.

n	a(n)
0	0
1	1
2	3
3	7
4	10
5	17
6	21
7	31
8	36
9	49
10	55
11	71
12	78
13	97
14	105
15	127
16	136
17	161
18	171
19	199
20	210
21	241
22	253
23	287
24	300
25	337
26	351
27	391
28	406
29	449
30	465
31	511
32	528
33	577
34	595
35	647
36	666
37	721
38	741
39	799
40	820
41	881
42	903
43	967
44	990
45	1057
46	1081
47	1151
48	1176
49	1249
50	1275
51	1351
52	1378
53	1457
54	1485

[0, 1, 3, 7, 10, 17, 21, 31, 36, 49, 55, 71, 78, 97, 105, 127, 136, 161, 171, 199, 210, 241, 253, 287, 300, 337, 351, 391, 406, 449, 465, 511, 528, 577, 595, 647, 666, 721, 741, 799, 820, 881, 903, 967, 990, 1057, 1081, 1151, 1176, 1249, 1275, 1351, 1378, 1457, 1485]

cp's OEIS Frontend

A128223 a(n) = if n mod 2 = 0 then n*(n+1)/2 otherwise (n+1)^2/2-1.

Table of values

List of values