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A232766
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Numbers n such that the concatenation n987654321 is prime.
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2
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28, 32, 44, 50, 55, 58, 97, 100, 107, 112, 130, 149, 152, 154, 179, 193, 208, 233, 259, 265, 271, 287, 310, 314, 320, 326, 341, 359, 365, 376, 404, 413, 421, 439, 449, 455, 457, 466, 469, 491, 499, 536, 538, 545, 547, 548, 557, 565, 568, 574, 593, 614, 616
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OFFSET
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1,1
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LINKS
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EXAMPLE
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314 is a member of this sequence because 314987654321 is prime.
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PROG
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(Python)
from sympy import isprime
{print(n, end=', ') for n in range(2000) if isprime(int(str(n)+"987654321"))}
(PARI) for(n=1, 2000, if(isprime(eval(concat(Str(n), "987654321"))), print1(n, ", "))) \\ Derek Orr, Apr 10 2015
(Magma) [n: n in [0..1000] | IsPrime(Seqint(Intseq(987654321) cat Intseq(n)))]; // Vincenzo Librandi, Apr 11 2015
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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