A354973 - cp's OEIS frontend

A354973 a(0)=0; for n > 0, a(n) = 2*a(n-1) if n-1 is prime, a(n-1) + 1 otherwise.

n	a(n)
0	0
1	1
2	2
3	4
4	8
5	9
6	18
7	19
8	38
9	39
10	40
11	41
12	82
13	83
14	166
15	167
16	168
17	169
18	338
19	339
20	678
21	679
22	680
23	681
24	1362
25	1363
26	1364
27	1365
28	1366
29	1367
30	2734
31	2735
32	5470
33	5471
34	5472
35	5473
36	5474
37	5475
38	10950
39	10951
40	10952
41	10953
42	21906
43	21907
44	43814
45	43815
46	43816
47	43817
48	87634

[0, 1, 2, 4, 8, 9, 18, 19, 38, 39, 40, 41, 82, 83, 166, 167, 168, 169, 338, 339, 678, 679, 680, 681, 1362, 1363, 1364, 1365, 1366, 1367, 2734, 2735, 5470, 5471, 5472, 5473, 5474, 5475, 10950, 10951, 10952, 10953, 21906, 21907, 43814, 43815, 43816, 43817, 87634]

cp's OEIS Frontend

A354973 a(0)=0; for n > 0, a(n) = 2*a(n-1) if n-1 is prime, a(n-1) + 1 otherwise.

Table of values

List of values