OFFSET
1,1
COMMENTS
By Xylouris' version of Linnik's theorem, a(n) << 3^(6.2^n + cn) for some constant c. [Charles R Greathouse IV, Dec 27 2011]
EXAMPLE
a(1) = 3;
a(2) = 23 because 2 is the smallest prime prefix and 23 is prime;
a(3) = 223 because 2 is the smallest prime prefix and 223 is prime;
a(4) = 31223 because 31 is the smallest prime prefix and 31223 is prime.
MAPLE
a0:=3: printf(`%d, `, a0):for it from 1 to 20 do: i:=0:for n from 1 to 1000 while(i=0) do:p0:=ithprime(n):n0:=length(a0):x:=p0*10^n0+a0: if type(x, prime)=true then printf(`%d, `, x):i:=1:a0:=x:else fi:od:od:
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Dec 27 2011
STATUS
approved