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Primes n of the form 100p+q with primes p and q, 98>p>q>10.
4

%I #6 Jun 08 2015 13:07:58

%S 1913,2311,2917,3119,3719,4111,4129,4337,4723,4729,5323,5347,5923,

%T 5953,6113,6131,6143,6719,6737,6761,7129,7159,7331,7919,7937,8311,

%U 8317,8329,8353,8923,8929,8941,8971,9719,9743,9767

%N Primes n of the form 100p+q with primes p and q, 98>p>q>10.

%C Or, primes that are concatenation of two 2-digit primes 98>p>q>10.

%C There are exactly 36 such primes.

%t Sort[Select[100Last[#]+First[#]&/@Subsets[Prime[Range[5,25]],{2}], PrimeQ]] (* _Harvey P. Dale_, Aug 19 2013 *)

%o (PARI) is(n)=isprime(n) && isprime(n\100) && isprime(n%100) && n<9768 \\ _Charles R Greathouse IV_, Jun 08 2015

%K fini,full,nonn,base,easy

%O 1,1

%A _Zak Seidov_, Nov 27 2009