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

1,1

Links

Table of n, a(n) for n=1..23.

Example

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.

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 *)

Prog

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

Crossrefs

Cf. A084667, A084669, A084670, A084671.

Sequence in context: A101219 A212238 A134820 * A126113 A282998 A213470

Adjacent sequences: A262202 A262203 A262204 * A262206 A262207 A262208

Keyword

nonn,easy,base

Author

Altug Alkan, Sep 15 2015

Status

approved