A216168 - cp's OEIS frontend

A216168 Composite numbers and 1 which yield a prime whenever a 7 is inserted anywhere in them, including at the beginning or end.

n	a(n)
1	1
2	9
3	27
4	33
5	39
6	57
7	87
8	159
9	177
10	187
11	603
12	717
13	753
14	949
15	1257
16	1707
17	2277
18	2367
19	4317
20	4623
21	4779
22	4797
23	5773
24	6757
25	6777
26	7017
27	7471
28	7479
29	7747
30	7797
31	7813
32	7977
33	8797
34	9777
35	9987
36	10777
37	11757
38	17679
39	28269
40	28437
41	29779
42	34177
43	34771
44	40059
45	41721

[1, 9, 27, 33, 39, 57, 87, 159, 177, 187, 603, 717, 753, 949, 1257, 1707, 2277, 2367, 4317, 4623, 4779, 4797, 5773, 6757, 6777, 7017, 7471, 7479, 7747, 7797, 7813, 7977, 8797, 9777, 9987, 10777, 11757, 17679, 28269, 28437, 29779, 34177, 34771, 40059, 41721]

cp's OEIS Frontend

A216168 Composite numbers and 1 which yield a prime whenever a 7 is inserted anywhere in them, including at the beginning or end.

Table of values

List of values