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A287244
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Indices n for which concatenation of the numbers from n to n + 9 is prime.
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2
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4, 20, 68, 88, 122, 140, 188, 200, 212, 220, 224, 244, 254, 374, 460, 490, 502, 518, 550, 568, 632, 688, 734, 814, 832, 884, 898, 908, 928, 982, 1022, 1108, 1472, 1490, 1498, 1514, 1544, 1580, 1894, 1954, 2074, 2230, 2294, 2384, 2492, 2524, 2722
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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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a(1) = 4, since 45678910111213 is prime.
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MAPLE
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filter:= proc(n) isprime(parse(cat($n .. n+9))) end proc:
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MATHEMATICA
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Position[Map[FromDigits@ Flatten@ IntegerDigits@ # &, Partition[Range@ 2800, 10, 1]], p_ /; PrimeQ@ p][[All, 1]] (* Michael De Vlieger, May 22 2017 *)
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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STATUS
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approved
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