A070742 - cp's OEIS frontend

A070742 a(n) = index of the (presumably) last palindrome in the 'Reverse and Add' trajectory of n, or -1 if this number is not finite, or 0 if no palindrome exists.

n	a(n)
1	18
2	17
3	32
4	16
5	36
6	31
7	30
8	15
9	23
10	35
11	34
12	30
13	33
14	29
15	29
16	14
17	32
18	22
19	28
20	34
21	30
22	33
23	29
24	29
25	14
26	32
27	22
28	28
29	27
30	30
31	33
32	29
33	29
34	14
35	32
36	22
37	28
38	27
39	28
40	33
41	29
42	29
43	14
44	32
45	22
46	28
47	27
48	28
49	26
50	29
51	29
52	14
53	32
54	22
55	28
56	27
57	28
58	26
59	13
60	29
61	14
62	32
63	22
64	28
65	27
66	28
67	26
68	13
69	27

[18, 17, 32, 16, 36, 31, 30, 15, 23, 35, 34, 30, 33, 29, 29, 14, 32, 22, 28, 34, 30, 33, 29, 29, 14, 32, 22, 28, 27, 30, 33, 29, 29, 14, 32, 22, 28, 27, 28, 33, 29, 29, 14, 32, 22, 28, 27, 28, 26, 29, 29, 14, 32, 22, 28, 27, 28, 26, 13, 29, 14, 32, 22, 28, 27, 28, 26, 13, 27]

cp's OEIS Frontend

A070742 a(n) = index of the (presumably) last palindrome in the 'Reverse and Add' trajectory of n, or -1 if this number is not finite, or 0 if no palindrome exists.

Table of values

List of values

n	a(n)
1	18
2	17
3	32
4	16
5	36
6	31
7	30
8	15
9	23
10	35
11	34
12	30
13	33
14	29
15	29
16	14
17	32
18	22
19	28
20	34
21	30
22	33
23	29
24	29
25	14
26	32
27	22
28	28
29	27
30	30
31	33
32	29
33	29
34	14
35	32
36	22
37	28
38	27
39	28
40	33
41	29
42	29
43	14
44	32
45	22
46	28
47	27
48	28
49	26
50	29
51	29
52	14
53	32
54	22
55	28
56	27
57	28
58	26
59	13
60	29
61	14
62	32
63	22
64	28
65	27
66	28
67	26
68	13
69	27

n	a(n)
1	18
2	17
3	32
4	16
5	36
6	31
7	30
8	15
9	23
10	35
11	34
12	30
13	33
14	29
15	29
16	14
17	32
18	22
19	28
20	34
21	30
22	33
23	29
24	29
25	14
26	32
27	22
28	28
29	27
30	30
31	33
32	29
33	29
34	14
35	32
36	22
37	28
38	27
39	28
40	33
41	29
42	29
43	14
44	32
45	22
46	28
47	27
48	28
49	26
50	29
51	29
52	14
53	32
54	22
55	28
56	27
57	28
58	26
59	13
60	29
61	14
62	32
63	22
64	28
65	27
66	28
67	26
68	13
69	27

n	a(n)
1	18
2	17
3	32
4	16
5	36
6	31
7	30
8	15
9	23
10	35
11	34
12	30
13	33
14	29
15	29
16	14
17	32
18	22
19	28
20	34
21	30
22	33
23	29
24	29
25	14
26	32
27	22
28	28
29	27
30	30
31	33
32	29
33	29
34	14
35	32
36	22
37	28
38	27
39	28
40	33
41	29
42	29
43	14
44	32
45	22
46	28
47	27
48	28
49	26
50	29
51	29
52	14
53	32
54	22
55	28
56	27
57	28
58	26
59	13
60	29
61	14
62	32
63	22
64	28
65	27
66	28
67	26
68	13
69	27