OFFSET
1,1
COMMENTS
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Andrica's Conjecture
Eric Weisstein's World of Mathematics, Legendre's Conjecture
Wikipedia, Andrica's conjecture
MATHEMATICA
Floor[2Sqrt[Prime[Range[70]]]+1] (* Harvey P. Dale, Sep 04 2020 *)
PROG
(Haskell)
a247485 = (+ 1) . floor . (* 2) . sqrt . fromIntegral . a000040
(PARI) a(n) = 1+sqrtint(4*prime(n)); \\ Michel Marcus, Aug 26 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Sep 20 2014
STATUS
approved