OFFSET
2,1
EXAMPLE
a(4)=12 because p(4)=7 and p(7)=17.
MAPLE
a:=n->(ithprime(n)+ithprime(ithprime(n)))/2: seq(a(n), n=2..70);
MATHEMATICA
Table[Mean[{Prime[n], Prime[Prime[n]]}], {n, 2, 60}] (* Harvey P. Dale, Jul 30 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Emeric Deutsch, Feb 20 2007
STATUS
approved