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A302987
Primes p such that p+3 divides 3^p+3.
1
3, 7, 727, 1595287, 3773335151, 53968982887, 218662611751, 373627441111, 525882352087, 612618285511
OFFSET
1,1
COMMENTS
Conjecture: the sequence is finite.
Is this the same as the primes in A251862? - Michel Marcus, Apr 17 2018
a(11) > 10^12, if it exists. - Giovanni Resta, Apr 17 2018
MATHEMATICA
Select[Prime[Range[10000]], Divisible[3^# + 3, # + 3] &] (* Vincenzo Librandi, Apr 17 2018 *)
PROG
(PARI) isok(p) = isprime(p) && (Mod(3, p+3)^p == Mod(-3, p+3)); \\ Michel Marcus, Apr 17 2018
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Alex Ratushnyak, Apr 17 2018
EXTENSIONS
a(4)-a(5) from Michel Marcus, Apr 17 2018
a(6)-a(10) from Giovanni Resta, Apr 17 2018
STATUS
approved