OFFSET
1,1
COMMENTS
Numbers n such that A255920(n) > 0.
Complement of A255921. - Felix Fröhlich, Dec 03 2020
LINKS
Felix Fröhlich, Table of n, a(n) for n = 1..10000
EXAMPLE
The prime 5 satisfies 24^(5-1) == 1 (mod 5^2) and 5 < 24, so 24 is a term of the sequence.
MATHEMATICA
Select[Range@ 94, Function[n, Count[Prime@ Range@ PrimePi@ n, p_ /; Mod[n^(p - 1), p^2] == 1] > 0]] (* Michael De Vlieger, May 30 2016 *)
PROG
(PARI) is(n) = forprime(p=1, n-1, if(Mod(n, p^2)^(p-1)==1, return(1))); 0
CROSSREFS
KEYWORD
nonn
AUTHOR
Felix Fröhlich, May 30 2016
STATUS
approved