OFFSET
1,1
COMMENTS
Average of n and n-th prime is a prime. All n must be odd.
LINKS
Paolo P. Lava, Table of n, a(n) for n = 1..1000
EXAMPLE
15 is in the list since (15+Prime(15))/2=31.
MATHEMATICA
Select[Range[632], PrimeQ[(# + Prime[#])/2] &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jayanta Basu, May 18 2013
STATUS
approved