OFFSET
1,2
EXAMPLE
k=1 is in the sequence because 2931k = 29311 is a prime number.
k=113 is in the sequence because 2931k = 2931113 is a prime number.
MATHEMATICA
Select[Range[1000], PrimeQ[#+2931 10^IntegerLength[#]]&] (* Harvey P. Dale, Sep 16 2011 *)
PROG
(Magma) [ n: n in [1..750] | IsPrime(Seqint(Intseq(n) cat [1, 3, 9, 2])) ]; // Vincenzo Librandi, Feb 02 2011
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Jun 25 2005
STATUS
approved