A255586 - cp's OEIS frontend

A255586 Composite k such that Sum_{i=1..t-1} d(i+1)/d(i) is an integer, where d(1), ..., d(t) are the divisors of k in ascending order.

n	a(n)
1	4
2	8
3	9
4	16
5	18
6	25
7	27
8	32
9	48
10	49
11	50
12	64
13	81
14	98
15	108
16	121
17	125
18	128
19	162
20	169
21	242
22	243
23	256
24	289
25	338
26	343
27	361
28	375
29	512
30	529
31	578
32	625
33	722
34	729
35	841
36	961
37	1024
38	1029
39	1058
40	1250
41	1331
42	1369
43	1458
44	1681
45	1682
46	1849
47	1920
48	1922
49	2048
50	2187
51	2197
52	2209

[4, 8, 9, 16, 18, 25, 27, 32, 48, 49, 50, 64, 81, 98, 108, 121, 125, 128, 162, 169, 242, 243, 256, 289, 338, 343, 361, 375, 512, 529, 578, 625, 722, 729, 841, 961, 1024, 1029, 1058, 1250, 1331, 1369, 1458, 1681, 1682, 1849, 1920, 1922, 2048, 2187, 2197, 2209]

cp's OEIS Frontend

A255586 Composite k such that Sum_{i=1..t-1} d(i+1)/d(i) is an integer, where d(1), ..., d(t) are the divisors of k in ascending order.

Table of values

List of values