OFFSET
1,1
COMMENTS
If q is an odd prime (p^2)! and q^(p^2)-1 are not relatively primes for any p prime.
Same as primes p where the smallest prime factor of M(p)=2^p-1 is less than p^2. - William Hu, Aug 18 2024
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= proc(p) local t, q, i;
if not isprime(p) then return false fi;
t:= 2^p-1;
igcd(t, convert(select(isprime, [seq(i, i=1..p^2, 2*p)]), `*`)) <> 1
end proc:
filter(2):= true:
select(filter, [2, seq(i, i=3..1000, 2)]); # Robert Israel, Aug 26 2024
MATHEMATICA
Select[Prime[Range[130]], !CoprimeQ[(#^2)!, 2^#^2-1]&] (* Harvey P. Dale, Jan 15 2022 *)
PROG
(PARI) forprime(n=1, 263, if(gcd((n^2)!, 2^(n^2)-1)>1, print1(n, ", ")))
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, May 06 2002
EXTENSIONS
More terms from Ralf Stephan, Oct 14 2002
STATUS
approved