A394394 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A394394 as a simple table

n	a(n)
1	0
2	1
3	3
4	6
5	10
6	15
7	21
8	28
9	36
10	45
11	55
12	66
13	78
14	91
15	105
16	120
17	136
18	153
19	171
20	190
21	210
22	231
23	253
24	276
25	300
26	325
27	349
28	376
29	404
30	433
31	463
32	492
33	524
34	557
35	591
36	626
37	662
38	699
39	737
40	776

[0,1,3,6,10,15,21,28,36,45,55,66,78,91,105,120, 136,153,171,190,210,231,253,276,300,325,349,376, 404,433,463,492,524,557,591,626,662,699,737,776]