A262205 Primes that are the concatenation of n, prime(n) and n.

353, 7177, 9239, 113111, 5324153, 5726957, 5927759, 6934769, 8141981, 9750997, 101547101, 123677123, 131739131, 153883153, 1791063179, 1891129189, 2011229201, 2071279207, 2311453231, 2491579249, 2631669263, 2691723269, 2791801279

Offset: 1

Author

Altug Alkan, Sep 15 2015

Keywords

• nonn
• easy
• base

Examples

			353 is a prime number that is concatenation of 3, prime(3) and 3.
7177 is a prime number that is concatenation of 7, prime(7) and 7.
9239 is a prime number that is concatenation of 9, prime(9) and 9.
		

Crossrefs

Cf. A084667, A084669, A084670, A084671.

Programs

Magma

[p: n in [1..400] | IsPrime(p) where p is Seqint(Intseq(n) cat Intseq(NthPrime(n)) cat Intseq(n))]; // Bruno Berselli, Sep 15 2015

Mathematica

f[n_] := Block[{d = IntegerDigits@ n, p = IntegerDigits@ Prime@ n}, FromDigits@ Join[d, p, d]]; Select[f /@ Range@ 300, PrimeQ] (* Michael De Vlieger, Sep 15 2015 *)

PARI

for(n=1, 1e3, if(isprime(k=eval(Str(n, prime(n), n))), print1(k", ")))