OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
a(6) = 1319 as 1317 is composite. prime(6) = 13.
MATHEMATICA
spc[n_]:=Module[{p1=Prime[n], p2}, p2=NextPrime[p1]; While[!PrimeQ[ p1* 10^IntegerLength[ p2]+p2], p2 = NextPrime[p2]]; p1*10^IntegerLength[ p2]+p2]; Array[spc, 40] (* Harvey P. Dale, Apr 05 2018 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 18 2005
EXTENSIONS
More terms from Stefan Steinerberger and Jim Nastos, Nov 18 2005
STATUS
approved