A257348 - cp's OEIS frontend

A257348 Repeatedly applying the map x -> sigma(x) partitions the natural numbers into a number of disjoint trees; sequence gives the (conjectural) list of minimal representatives of these trees.

n	a(n)
1	1
2	2
3	5
4	16
5	19
6	27
7	29
8	33
9	49
10	50
11	52
12	66
13	81
14	85
15	105
16	146
17	147
18	163
19	170
20	189
21	197
22	199
23	218
24	226
25	243
26	262
27	303
28	315
29	343
30	424
31	430
32	438
33	453
34	461
35	463
36	469
37	472
38	484
39	489
40	513
41	530
42	550
43	584
44	677
45	722
46	746
47	786
48	787
49	804
50	813
51	821
52	831
53	842
54	859
55	867
56	876
57	892
58	903
59	914
60	916
61	937
62	977
63	982
64	988
65	990
66	1029

[1, 2, 5, 16, 19, 27, 29, 33, 49, 50, 52, 66, 81, 85, 105, 146, 147, 163, 170, 189, 197, 199, 218, 226, 243, 262, 303, 315, 343, 424, 430, 438, 453, 461, 463, 469, 472, 484, 489, 513, 530, 550, 584, 677, 722, 746, 786, 787, 804, 813, 821, 831, 842, 859, 867, 876, 892, 903, 914, 916, 937, 977, 982, 988, 990, 1029]

cp's OEIS Frontend

A257348 Repeatedly applying the map x -> sigma(x) partitions the natural numbers into a number of disjoint trees; sequence gives the (conjectural) list of minimal representatives of these trees.

Table of values

List of values