OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..1000
EXAMPLE
101 is the average of 81 and 121.
MATHEMATICA
a = Select[ Range[2, 10000000], ! PrimeQ[ # ] && Length[FactorInteger[ # ]] == 1 &]; sizea = Length[a]; (a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &]]] + a[[Select[Range[sizea - 1], PrimeQ[(a[[ # ]] + a[[ # + 1]])/2] &] + 1]])/2
CROSSREFS
KEYWORD
nonn
AUTHOR
Tanya Khovanova, Sep 15 2007
EXTENSIONS
More terms from Amiram Eldar, Feb 18 2022
STATUS
approved