OFFSET
1,1
COMMENTS
Some twin prime terms are (149,151), (311,313), (419,421), (659,661), ... Conjecture: there are infinitely many twin primes in this sequence.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
563 is a term because it is prime and 10^3 - 563 = 437 = 19*23.
MATHEMATICA
Select[Prime[Range[200]], PrimeOmega[10^IntegerLength[#]-#]==2&] (* Harvey P. Dale, Oct 13 2011 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Jason Earls, Jul 09 2005
STATUS
approved