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A085720
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Start of a run of 7 successive numbers which when concatenated form a prime.
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1
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7, 37, 157, 185, 187, 271, 301, 355, 475, 485, 523, 533, 577, 611, 653, 661, 667, 731, 733, 755, 761, 791, 853, 911, 913, 937, 983, 1085, 1111, 1187, 1205, 1253, 1397, 1417, 1585, 1631, 1655, 1685, 1697, 1711, 1723, 1841, 1907, 1975, 2035, 2077, 2105, 2185
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OFFSET
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1,1
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COMMENTS
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Concatenation of three and six successive numbers are always composite.
Primes as concatenation of two, four and five successive numbers are in A030458, A030471, A052087, A052088, A052089.
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LINKS
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Harvey P. Dale, Table of n, a(n) for n = 1..1000
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MATHEMATICA
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f[n_] := FromDigits[ Flatten[ Table[ IntegerDigits[i], {i, n, n + 6}]]]; Select[ Range[2190], PrimeQ[ f[ # ]] & ]
Select[Range[2500], PrimeQ[FromDigits[Flatten[IntegerDigits/@Range[#, #+6]]]]&] (* Harvey P. Dale, Aug 15 2021 *)
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CROSSREFS
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Cf. A030458, A030471, A052087, A052088, A052089.
Sequence in context: A202119 A201083 A036678 * A201962 A269257 A269258
Adjacent sequences: A085717 A085718 A085719 * A085721 A085722 A085723
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KEYWORD
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easy,nonn,base
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AUTHOR
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Zak Seidov, Jun 27 2003
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EXTENSIONS
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Edited by Robert G. Wilson v, Jun 28 2003
Edited by Charles R Greathouse IV, Apr 24 2010
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STATUS
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approved
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