OFFSET
1,2
LINKS
Daniel Starodubtsev, Table of n, a(n) for n = 1..10000
EXAMPLE
37 is a member as 37337 and 3373 are both prime.
MATHEMATICA
Select[Range[2000], PrimeQ[FromDigits @ Join[(d = IntegerDigits[#]), {3}, d]] && PrimeQ[FromDigits @ Join[{3}, d, {3}]] &] (* Amiram Eldar, Dec 07 2019 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 28 2003
EXTENSIONS
More terms from mohammed bouayoun (bouyao(AT)wanadoo.fr), Feb 02 2004
STATUS
approved