A064081 - cp's OEIS frontend

A064081 Zsigmondy numbers for a = 5, b = 1: Zs(n, 5, 1) is the greatest divisor of 5^n - 1^n (A024049) that is relatively prime to 5^m - 1^m for all positive integers m < n.

n	a(n)
1	4
2	3
3	31
4	13
5	781
6	7
7	19531
8	313
9	15751
10	521
11	12207031
12	601
13	305175781
14	13021
15	315121
16	195313
17	190734863281
18	5167
19	4768371582031
20	375601
21	196890121
22	8138021
23	2980232238769531
24	390001
25	95397958987501
26	203450521
27	3814699218751
28	234750601
29	46566128730773925781
30	464881
31	1164153218269348144531

[4, 3, 31, 13, 781, 7, 19531, 313, 15751, 521, 12207031, 601, 305175781, 13021, 315121, 195313, 190734863281, 5167, 4768371582031, 375601, 196890121, 8138021, 2980232238769531, 390001, 95397958987501, 203450521, 3814699218751, 234750601, 46566128730773925781, 464881, 1164153218269348144531]

cp's OEIS Frontend

A064081 Zsigmondy numbers for a = 5, b = 1: Zs(n, 5, 1) is the greatest divisor of 5^n - 1^n (A024049) that is relatively prime to 5^m - 1^m for all positive integers m < n.

Table of values

List of values