OFFSET
1,1
EXAMPLE
373 becomes 3(0)7(0)3 which is prime 30703.
MATHEMATICA
(* This program works in Mathematica 6.0 and later *)
Select[Range[11, 1000, 2], PrimeQ[FromDigits[Riffle[IntegerDigits[#], 0]]] &] (* T. D. Noe, Dec 22 2010 *)
(* The following program has been tested in Mathematica 5.1 and it works *)
Reap[c = 0; d = 0; Do[If[MemberQ[{1, 3, 7, 9}, Mod[n, 10]], id = IntegerDigits[n]; Do[id[[k]] = {id[[k]], d}, {k, Length[id] - 1}]; If[PrimeQ[FromDigits[Flatten[id]]], Sow[n]; c++; If[c > 999, Break[]]]], {n, 11, 20000}]][[2, 1]] (* Zak Seidov, Dec 22 2010 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Aug 15 1999
EXTENSIONS
Offset set to 1 by Georg Fischer, Oct 15 2019
STATUS
approved