A085414 - OEIS

%I #7 Oct 05 2013 02:10:46

%S 131,191,313,373,797,1031,1091,1511,1571,1811,1931,3313,3373,3533,

%T 3593,3673,3733,3793,3833,7517,7577,7877,9199,9419,9479,9539,9679,

%U 9719,9839,10091,10211,10331,10391,10631,10691,11171,12011,12491,12791,12911

%N Primes that are a concatenation of a prime and its first digit.

%C Also primes remaining prime after deleting last digit, but not all such primes. See also A012833, A024770, A033664, A069867.

%e 13 is a term because concatenation of 13 and 1 is prime.

%Y Cf. A085412, A085413, A012833, A024770, A033664, A069867.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Jun 29 2003