A173281 - cp's OEIS frontend

A173281 Let a(1) = 1. Given a(1), ..., a(2^t), find the least k such that a(1) + 2^k, a(2) + 2^k, ..., a(2^t) + 2^k are all composite and a(1) + 2^k > a(2^t). Then a(2^t+i) = a(i) + 2^k for all 1 <= i <= 2^t.

n	a(n)
1	1
2	9
3	2049
4	2057
5	4097
6	4105
7	6145
8	6153
9	524289
10	524297
11	526337
12	526345
13	528385
14	528393
15	530433
16	530441
17	16777217
18	16777225
19	16779265
20	16779273
21	16781313
22	16781321
23	16783361
24	16783369
25	17301505
26	17301513
27	17303553
28	17303561
29	17305601
30	17305609
31	17307649
32	17307657

[1, 9, 2049, 2057, 4097, 4105, 6145, 6153, 524289, 524297, 526337, 526345, 528385, 528393, 530433, 530441, 16777217, 16777225, 16779265, 16779273, 16781313, 16781321, 16783361, 16783369, 17301505, 17301513, 17303553, 17303561, 17305601, 17305609, 17307649, 17307657]

cp's OEIS Frontend

A173281 Let a(1) = 1. Given a(1), ..., a(2^t), find the least k such that a(1) + 2^k, a(2) + 2^k, ..., a(2^t) + 2^k are all composite and a(1) + 2^k > a(2^t). Then a(2^t+i) = a(i) + 2^k for all 1 <= i <= 2^t.

Table of values

List of values