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A262205 Primes that are the concatenation of n, prime(n) and n. 2
353, 7177, 9239, 113111, 5324153, 5726957, 5927759, 6934769, 8141981, 9750997, 101547101, 123677123, 131739131, 153883153, 1791063179, 1891129189, 2011229201, 2071279207, 2311453231, 2491579249, 2631669263, 2691723269, 2791801279 (list; graph; refs; listen; history; text; internal format)
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

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Last modified September 21 13:37 EDT 2019. Contains 327253 sequences. (Running on oeis4.)