OFFSET
1,1
COMMENTS
If p = 2^k - 3 is in this sequence, then p*2^(k-1) is abundant with abundance 2. - Claude Morin, Feb 01 2007
Equivalently, primes which give a prime number when 0's and 1's are interchanged in their binary representation; note that the resulting prime is always 10_2 = 2_10 (see A347476). - Bernard Schott, Nov 14 2021
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..30
FORMULA
a(n) = 2^A050414(n) - 3.
MATHEMATICA
lst={}; Do[p=2^n-3; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 5*5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 27 2009 *)
Select[Table[2^n-3, {n, 1, 400}], PrimeQ] (* Vincenzo Librandi, Dec 08 2011 *)
PROG
(Magma) [a: n in [1..200] | IsPrime(a) where a is 2^n-3]; // Vincenzo Librandi, Dec 08 2011
(PARI) for(n=3, 999, if(ispseudoprime(t=2^n-3), print1(t", "))) \\ Charles R Greathouse IV, Jul 02 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Jud McCranie, Dec 22 1999
STATUS
approved