A213912 - cp's OEIS frontend

A213912 a(1) = 1; for n>1, a(n) = floor(sqrt(a(n-1))) if that number is not already in the sequence, otherwise a(n) = 3*a(n-1).

n	a(n)
1	1
2	3
3	9
4	27
5	5
6	2
7	6
8	18
9	4
10	12
11	36
12	108
13	10
14	30
15	90
16	270
17	16
18	48
19	144
20	432
21	20
22	60
23	7
24	21
25	63
26	189
27	13
28	39
29	117
30	351
31	1053
32	32
33	96
34	288
35	864
36	29
37	87
38	261
39	783
40	2349
41	7047
42	83
43	249
44	15
45	45
46	135
47	11
48	33
49	99
50	297
51	17
52	51
53	153
54	459
55	1377
56	37
57	111
58	333
59	999
60	31

[1, 3, 9, 27, 5, 2, 6, 18, 4, 12, 36, 108, 10, 30, 90, 270, 16, 48, 144, 432, 20, 60, 7, 21, 63, 189, 13, 39, 117, 351, 1053, 32, 96, 288, 864, 29, 87, 261, 783, 2349, 7047, 83, 249, 15, 45, 135, 11, 33, 99, 297, 17, 51, 153, 459, 1377, 37, 111, 333, 999, 31]

cp's OEIS Frontend

A213912 a(1) = 1; for n>1, a(n) = floor(sqrt(a(n-1))) if that number is not already in the sequence, otherwise a(n) = 3*a(n-1).

Table of values

List of values