A242170 - cp's OEIS frontend

A242170 Least prime divisor of T(n) which does not divide any T(k) with k < n, or 1 if such a primitive prime divisor of T(n) does not exist, where T(n) is the n-th central trinomial coefficient given by A002426.

n	a(n)
1	1
2	3
3	7
4	19
5	17
6	47
7	131
8	41
9	43
10	1279
11	503
12	113
13	2917
14	569
15	198623
16	14083
17	26693
18	201611
19	42998951
20	41931041
21	52635749
22	1296973
23	169097
24	1451
25	1304394227
26	107
27	233
28	173
29	2062225210273
30	719
31	191
32	31551555041
33	6301
34	563
35	3769
36	967
37	9539
38	5073466546857451
39	4542977
40	9739

[1, 3, 7, 19, 17, 47, 131, 41, 43, 1279, 503, 113, 2917, 569, 198623, 14083, 26693, 201611, 42998951, 41931041, 52635749, 1296973, 169097, 1451, 1304394227, 107, 233, 173, 2062225210273, 719, 191, 31551555041, 6301, 563, 3769, 967, 9539, 5073466546857451, 4542977, 9739]

cp's OEIS Frontend

A242170 Least prime divisor of T(n) which does not divide any T(k) with k < n, or 1 if such a primitive prime divisor of T(n) does not exist, where T(n) is the n-th central trinomial coefficient given by A002426.

Table of values

List of values