A320224 - cp's OEIS frontend

A320224 a(1) = 1; a(n > 1) = Sum_{k = 1..n-1} Sum_{d|k, d < k} a(d).

n	a(n)
1	1
2	0
3	1
4	2
5	3
6	4
7	6
8	7
9	10
10	12
11	16
12	17
13	25
14	26
15	33
16	38
17	48
18	49
19	65
20	66
21	84
22	92
23	109
24	110
25	142
26	146
27	172
28	184
29	219
30	220
31	274
32	275
33	323
34	341
35	390
36	400
37	484
38	485
39	551
40	578
41	669
42	670
43	792
44	793
45	904
46	952
47	1062
48	1063
49	1243
50	1250
51	1408
52	1458
53	1632
54	1633
55	1870
56	1890

[1, 0, 1, 2, 3, 4, 6, 7, 10, 12, 16, 17, 25, 26, 33, 38, 48, 49, 65, 66, 84, 92, 109, 110, 142, 146, 172, 184, 219, 220, 274, 275, 323, 341, 390, 400, 484, 485, 551, 578, 669, 670, 792, 793, 904, 952, 1062, 1063, 1243, 1250, 1408, 1458, 1632, 1633, 1870, 1890]

cp's OEIS Frontend

A320224 a(1) = 1; a(n > 1) = Sum_{k = 1..n-1} Sum_{d|k, d < k} a(d).

Table of values

List of values