OFFSET
1,1
LINKS
Daniel Starodubtsev, Table of n, a(n) for n = 1..10000
Peter Alfeld, The 10,000 smallest prime numbers.
EXAMPLE
2357 is a prime of order four since it is concatenated from the primes 2,3,5 and 7.
MATHEMATICA
Select[ Table[ FromDigits[ Flatten[ IntegerDigits /@ {2, 3, 5, Prime[n]}]], {n, 200}], PrimeQ[ # ] &] (* Robert G. Wilson v, Dec 20 2004 *)
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Parthasarathy Nambi, Dec 16 2004
EXTENSIONS
Extended by Ray Chandler and Robert G. Wilson v, Dec 22 2004
STATUS
approved