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A053546
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Smallest prime containing a leading sequence of n ascending numbers.
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5
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11, 127, 1231, 12343, 123457, 12345623, 123456719, 1234567801, 1234567891, 1234567891003, 12345678910111, 12345678910111207, 1234567891011121309, 123456789101112131449, 12345678910111213141523, 123456789101112131415161, 123456789101112131415161717
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OFFSET
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1,1
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COMMENTS
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The Magma Calculator (http://magma.maths.usyd.edu.au/calc/) verified each of the 100 terms in the table as prime. - Jon E. Schoenfield, Aug 24 2009
Can this sequence be proved to be infinite, a sort of Dirichlet's Theorem in reverse? - Charles R Greathouse IV, Jul 23 2011
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LINKS
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EXAMPLE
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a(6) = 12345623 is the smallest prime beginning with the string 123456.
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MATHEMATICA
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sp[n_]:=Module[{m=1, np}, np=NextPrime[n*10^m]; While[Floor[np/10^m] != n, m++; np=NextPrime[n*10^m]]; np]; sp/@Table[FromDigits[ Flatten[ IntegerDigits/@ Range[x]]], {x, 20}] (* Harvey P. Dale, May 22 2016 *)
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CROSSREFS
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KEYWORD
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base,easy,nice,nonn
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AUTHOR
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STATUS
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approved
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