OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
a(5)=23 because 19 is prime and 23 - floor(sqrt(23)) = 23 - floor(4.795831523) = 23 - 4 = 19, which is prime.
MATHEMATICA
f[n_]:=n-Floor[Sqrt[n]]; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], AppendTo[lst, p]], {n, 7!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 25 2010 *)
Select[Prime[Range[300]], PrimeQ[#-Floor[Sqrt[#]]]&] (* Harvey P. Dale, Sep 26 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Chuck Seggelin (barkeep(AT)plastereddragon.com), Jul 08 2003
EXTENSIONS
More terms from Vladimir Joseph Stephan Orlovsky, Feb 25 2010
STATUS
approved