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A232728 Primes p such that the concatenation p123456789 is prime. 2
41, 59, 179, 193, 241, 409, 439, 613, 653, 661, 719, 739, 787, 853, 881, 887, 997, 1091, 1103, 1129, 1181, 1213, 1381, 1409, 1459, 1487, 1489, 1571, 1579, 1669, 1741, 1801, 1823, 1861, 1871, 1879, 1889, 1907, 1913, 1993, 2039, 2083, 2099, 2243, 2417, 2593, 2659, 2663, 2729, 2741, 2833, 3079, 3119 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in A232727.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

59 is a member of this sequence because 59 is prime and 59123456789 is prime.

MATHEMATICA

With[{r=Range[1, 9]}, Select[Prime[Range[500]], PrimeQ[FromDigits[Join[IntegerDigits[#], r]]]&]] (* Vincenzo Librandi, Apr 28 2015 *)

Select[Prime[Range[500]], PrimeQ[#*10^9+123456789]&] (* Harvey P. Dale, Apr 01 2018 *)

PROG

(Python)

from sympy import prime, isprime

{print(prime(n), end=', ') for n in range(1, 10**3) if isprime(int(str(prime(n))+'123456789'))}

## Simplified by Derek Orr, Apr 28 2015

(PARI) forprime(p=1, 10^4, if(isprime(eval(concat(Str(p), "123456789"))), print1(p, ", "))) \\ Derek Orr, Apr 28 2015

(MAGMA) [p: p in PrimesUpTo(5000) | IsPrime(Seqint(Intseq(123456789) cat Intseq(p)))]; // Vincenzo Librandi, Apr 28 2015

CROSSREFS

Cf. A232727, A104914, A104915.

Sequence in context: A139890 A082932 A290005 * A113338 A222577 A116322

Adjacent sequences:  A232725 A232726 A232727 * A232729 A232730 A232731

KEYWORD

nonn,base,easy

AUTHOR

Derek Orr, Nov 29 2013

EXTENSIONS

More terms from Derek Orr, Apr 28 2015

STATUS

approved

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Last modified July 5 19:02 EDT 2020. Contains 335473 sequences. (Running on oeis4.)