A240588 - cp's OEIS frontend

A240588 a(1) = 1, a(2) = 2; for n >= 3, a(n) = least number not included earlier that divides the concatenation of all previous terms.

n	a(n)
1	1
2	2
3	3
4	41
5	7
6	9
7	137131
8	61
9	2023244487101
10	13
11	19
12	11
13	143
14	142733
15	21
16	17
17	193
18	37
19	3907
20	1290366811360047359
21	1805030483980039
22	3803623
23	123
24	369
25	27
26	23
27	58271
28	47609
29	523
30	79
31	307
32	179
33	73
34	57
35	18032419296851
36	29
37	31
38	3281881401611107
39	69
40	171
41	60244474373
42	197
43	97

[1, 2, 3, 41, 7, 9, 137131, 61, 2023244487101, 13, 19, 11, 143, 142733, 21, 17, 193, 37, 3907, 1290366811360047359, 1805030483980039, 3803623, 123, 369, 27, 23, 58271, 47609, 523, 79, 307, 179, 73, 57, 18032419296851, 29, 31, 3281881401611107, 69, 171, 60244474373, 197, 97]

cp's OEIS Frontend

A240588 a(1) = 1, a(2) = 2; for n >= 3, a(n) = least number not included earlier that divides the concatenation of all previous terms.

Table of values

List of values