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A288021
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Prime p1 of consecutive primes p1, p2, where p2 - p1 = 4, and p1, p2 are in different decades.
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4
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7, 19, 37, 67, 79, 97, 109, 127, 229, 277, 307, 349, 379, 397, 439, 457, 487, 499, 739, 757, 769, 859, 877, 907, 937, 967, 1009, 1087, 1279, 1297, 1429, 1447, 1489, 1549, 1567, 1579, 1597, 1609, 1867, 1999, 2137, 2239, 2269, 2347, 2377, 2389, 2437, 2539, 2617, 2659, 2689, 2707, 2749, 2797, 2857
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OFFSET
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1,1
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COMMENTS
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The unit digits of the numbers in the sequence are 7's or 9's.
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LINKS
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EXAMPLE
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7 is in this sequence since pair (7,11) is the first with difference 4 spanning a multiple of 10.
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MATHEMATICA
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a288021[n_] := Map[Last, Select[Map[{NextPrime[#, 1], NextPrime[#, -1]}&, Range[10, n, 10]], First[#]-Last[#]==4&]]
a288021[3000] (* data *)
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CROSSREFS
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Cf. A001359, A023201, A023203, A031924, A031925, A031928, A046117, A046132, A158277, A158861, A160370, A160440, A160500, A287049, A287050, A060229, A288022, A288024.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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