|
|
A328230
|
|
Numbers m that divide 3^(m + 1) + 1.
|
|
4
|
|
|
1, 2, 4, 5, 14, 244, 365, 434, 854, 2294, 3794, 5966, 7874, 10877, 26474, 33914, 117614, 188774, 231434, 284354, 487634, 501038, 589154, 593774, 621674, 755594, 1255814, 1306934, 1642094, 1911194, 2193124, 2434754, 2484674, 2507834, 2621654, 2643494, 3512114, 3759854, 3997574, 4082246
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Conjecture: For k > 2, k^(m + 1) == -1 (mod m) has an infinite number of positive solutions.
|
|
LINKS
|
|
|
MAPLE
|
filter:= m -> 3 &^ (m+1) + 1 mod m = 0:
|
|
PROG
|
(Magma) [n+1: n in [0..5000000] | Modexp(3, n+2, n+1) eq n];
(PARI) isok(m) = Mod(3, m)^(m+1) == -1; \\ Michel Marcus, Oct 10 2019
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|