OFFSET
1,1
COMMENTS
Primes p that divide 2^(2^(p-1)-1) - 1 are the same terms. Proof: p | 2^(2^(p-1)-1) - 1 iff ord_{p}(2) | 2^(p-1)-1, so p^2 | 2^(2^(p-1)-1) - 1, since p | 2^(p-1)-1 by FLT. - Thomas Ordowski, Sep 16 2024
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..200 from Arkadiusz Wesolowski)
MAPLE
isA188465 := proc(p) local m; if isprime(p) then m := modp(2 &^ ( (2 ^ (p-1))-1)-1, p) ; m := simplify(m) ; if m = 0 then true; else false; end if; else false; end if; end proc:
for i from 1 do p := ithprime(i) ; if isA188465(p) then printf("%d\n", p) ; end if; end do: # R. J. Mathar, Apr 10 2011
MATHEMATICA
okQ[p_] := Module[{k = MultiplicativeOrder[2, p^2]}, PowerMod[2, p - 1, k] == 1]; Select[Prime[Range[5000]], okQ] (* T. D. Noe, Apr 11 2011 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Arkadiusz Wesolowski, Apr 10 2011
STATUS
approved