OFFSET
1,1
COMMENTS
Primes can only occur for m=2^k. The next term (if it exists) has k >= 21 (i.e., more than 10^6 decimal digits). - Don Reble, Apr 28 2004. [For the latest results about the search, see A171381. - N. J. A. Sloane, Jun 14 2010]
a(7) >= (3^(2^24) + 1)/2, if it exists. - Tyler Busby, Mar 22 2023
EXAMPLE
a(3)=41 because it can be written as (3^4 + 1)/2 = 82/2.
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Hugo Pfoertner, Apr 19 2004
EXTENSIONS
Erroneous terms deleted by N. J. A. Sloane, Jun 14 2010
STATUS
approved