OFFSET
1,1
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
EXAMPLE
a(5) = 119 because the 5th prime is 11 and the 5th nonprime is 9.
PROG
(PARI) nprime(n)=c=0; k=1; while(k, if(!isprime(k), c++); if(c==n, return(k)); k++)
vector(50, n, eval(concat(Str(prime(n)), Str(nprime(n))))) \\ Derek Orr, Feb 06 2015
(Haskell)
import Data.Function (on)
a253911 n = a253911_list !! (n-1)
a253911_list = map read $
zipWith ((++) `on` show) a018252_list a000040_list :: [Integer]
-- Reinhard Zumkeller, Feb 09 2015
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Omar E. Pol, Feb 06 2015
STATUS
approved