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%I #15 Sep 08 2022 08:45:40
%S 2,17,23,41,61,71,83,127,227,337,353,499,503,571,727,887,911,937,971,
%T 1061,1427,1579,1663,1693,1709,1871,1877,1907,1949,1973,2017,2063,
%U 2081,2239,2339,2393,2467,2713,2797,2939,2999,3181,3271,3463,3643,3659,3677
%N Primes p such that the concatenation of p and prime(p) is prime.
%H Vincenzo Librandi, <a href="/A154963/b154963.txt">Table of n, a(n) for n = 1..1000</a>
%e Concatenation of prime 2 and second prime 3 is the prime 23, hence 2 is in the sequence.
%e Concatenation of prime 23 and 23rd prime 83 is the prime 2383, hence 23 is in the sequence.
%t A154963 = Select[ Prime[ Range[ 550 ] ], PrimeQ[ FromDigits[ Join[ IntegerDigits[ # ], IntegerDigits[ Prime[ # ] ] ] ] ] & ] (* _Alonso del Arte_ Nov 12 2009 *)
%o (Magma) [ p: p in PrimesUpTo(3700) | IsPrime(StringToInteger(IntegerToString(p) cat IntegerToString(NthPrime(p)))) ];
%Y Cf. A045532, A155032 (resulting primes).
%K nonn,base,easy,less
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 18 2009
%E Edited and extended beyond a(3) by _Klaus Brockhaus_, Jan 20 2009
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