OFFSET
1,3
LINKS
Peter Kagey, Table of n, a(n) for n = 1..10011 (first 141 rows, flattened)
EXAMPLE
Triangle begins:
n\k| 0 1 2 3 4 5 6 7 8 9
---+--------------------------------
1 | 1;
2 | 1, 2;
3 | 1, 3, 2;
4 | 1, 4, 2, 3;
5 | 1, 5, 2, 3, 2;
6 | 1, 6, 4, 6, 4, 6;
7 | 1, 7, 2, 3, 4, 3, 2;
8 | 1, 8, 2, 5, 2, 5, 2, 5;
9 | 1, 9, 2, 3, 4, 3, 2, 7, 2;
10 | 1, 10, 4, 6, 4, 10, 4, 6, 4, 10;
...
T(10,2) = 4 because
0^2 - 0 == 0 (mod 10),
1^2 - 1 == 0 (mod 10),
5^2 - 5 == 0 (mod 10), and
6^2 - 6 == 0 (mod 10).
PROG
(Haskell)
a337632t n k = length $ filter (\m -> (m^k - m) `mod` n == 0) [0..n-1]
(PARI) T(n, k) = sum(m=0, n-1, Mod(m, n)^k == Mod(m, n)); \\ Michel Marcus, Sep 13 2020
(Magma) [[#[m: m in [0..n-1] | m^k mod n eq m]: k in [0..n-1]]: n in [1..17]]; // Juri-Stepan Gerasimov, Oct 12 2020
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Peter Kagey, Sep 12 2020
STATUS
approved