A260597 - cp's OEIS frontend

A260597 Primes as they occur for the first time as factors of terms of A173426 = concatenation(1,2,...,n,n-1,...,1).

n	a(n)
1	11
2	3
3	37
4	101
5	41
6	271
7	7
8	13
9	239
10	4649
11	73
12	137
13	333667
14	12345678910987654321
15	17636684157301569664903
16	2799473675762179389994681
17	1109
18	4729
19	2354041513534224607850261
20	571
21	3167
22	10723
23	439781
24	2068140300159522133
25	75401
26	687437
27	759077450603

[11, 3, 37, 101, 41, 271, 7, 13, 239, 4649, 73, 137, 333667, 12345678910987654321, 17636684157301569664903, 2799473675762179389994681, 1109, 4729, 2354041513534224607850261, 571, 3167, 10723, 439781, 2068140300159522133, 75401, 687437, 759077450603]

cp's OEIS Frontend

A260597 Primes as they occur for the first time as factors of terms of A173426 = concatenation(1,2,...,n,n-1,...,1).

Table of values

List of values