A256705 - cp's OEIS frontend

A256705 Numbers n such that if we define f(n,m) by the recursion f(n,1)=n, f(n,k+1)= A007672(n,k), the subsequence f(n,k), with n constant, is eventually periodic with period two.

n	a(n)
1	9
2	16
3	25
4	45
5	49
6	63
7	75
8	80
9	81
10	99
11	112
12	117
13	121
14	125
15	128
16	147
17	153
18	169
19	171
20	175
21	176
22	207
23	208
24	225
25	243
26	245
27	250
28	256
29	261
30	275
31	279
32	289
33	304
34	315
35	325
36	333
37	343
38	361
39	363
40	368
41	369
42	375
43	387
44	405
45	423
46	425
47	441
48	464
49	475
50	477
51	486
52	495
53	496
54	500
55	507
56	512
57	525
58	529
59	531
60	539
61	549
62	560

[9, 16, 25, 45, 49, 63, 75, 80, 81, 99, 112, 117, 121, 125, 128, 147, 153, 169, 171, 175, 176, 207, 208, 225, 243, 245, 250, 256, 261, 275, 279, 289, 304, 315, 325, 333, 343, 361, 363, 368, 369, 375, 387, 405, 423, 425, 441, 464, 475, 477, 486, 495, 496, 500, 507, 512, 525, 529, 531, 539, 549, 560]

cp's OEIS Frontend

A256705 Numbers n such that if we define f(n,m) by the recursion f(n,1)=n, f(n,k+1)= A007672(n,k), the subsequence f(n,k), with n constant, is eventually periodic with period two.

Table of values

List of values

n	a(n)
1	9
2	16
3	25
4	45
5	49
6	63
7	75
8	80
9	81
10	99
11	112
12	117
13	121
14	125
15	128
16	147
17	153
18	169
19	171
20	175
21	176
22	207
23	208
24	225
25	243
26	245
27	250
28	256
29	261
30	275
31	279
32	289
33	304
34	315
35	325
36	333
37	343
38	361
39	363
40	368
41	369
42	375
43	387
44	405
45	423
46	425
47	441
48	464
49	475
50	477
51	486
52	495
53	496
54	500
55	507
56	512
57	525
58	529
59	531
60	539
61	549
62	560

n	a(n)
1	9
2	16
3	25
4	45
5	49
6	63
7	75
8	80
9	81
10	99
11	112
12	117
13	121
14	125
15	128
16	147
17	153
18	169
19	171
20	175
21	176
22	207
23	208
24	225
25	243
26	245
27	250
28	256
29	261
30	275
31	279
32	289
33	304
34	315
35	325
36	333
37	343
38	361
39	363
40	368
41	369
42	375
43	387
44	405
45	423
46	425
47	441
48	464
49	475
50	477
51	486
52	495
53	496
54	500
55	507
56	512
57	525
58	529
59	531
60	539
61	549
62	560

n	a(n)
1	9
2	16
3	25
4	45
5	49
6	63
7	75
8	80
9	81
10	99
11	112
12	117
13	121
14	125
15	128
16	147
17	153
18	169
19	171
20	175
21	176
22	207
23	208
24	225
25	243
26	245
27	250
28	256
29	261
30	275
31	279
32	289
33	304
34	315
35	325
36	333
37	343
38	361
39	363
40	368
41	369
42	375
43	387
44	405
45	423
46	425
47	441
48	464
49	475
50	477
51	486
52	495
53	496
54	500
55	507
56	512
57	525
58	529
59	531
60	539
61	549
62	560