OFFSET
1,1
COMMENTS
Subsequence of A144487.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..26
FORMULA
a(n) = 4^A253773(n) + 15. - Elmo R. Oliveira, Nov 28 2023
EXAMPLE
65551 is a term because 4^8 + 15 = 65551 is prime.
MATHEMATICA
Select[Table[4^n + 15, {n, 1, 200}], PrimeQ]
PROG
(Magma) [a: n in [1..70] | IsPrime(a) where a is 4^n+15];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Feb 22 2014
STATUS
approved