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A208892
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Two distinct sets of n consecutive numbers with identical corresponding prime signatures.
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3
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2, 3, 6, 7, 10, 11, 11, 12, 13, 17, 18, 19, 68, 69, 70, 71, 76, 77, 78, 79, 130, 131, 132, 133, 134, 138, 139, 140, 141, 142, 88, 89, 90, 91, 92, 93, 232, 233, 234, 235, 236, 237, 658, 659, 660, 661, 662, 663, 664, 1090, 1091, 1092, 1093, 1094, 1095, 1096
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OFFSET
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1,1
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COMMENTS
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The sets are chosen to minimize the larger of the two start values, so for example, (6,7) and (10,11) would be chosen over (5,6) and (13,14) since 10 is less than 13.
The sequence can be read as follows:
2, 3,
6,7, 10,11,
11,12,13, 17,18,19,
68,69,70,71, 76,77,78,79,
130,131,132,133,134, 138,139,140,141,142
88,89,90,91,92,93, 232,233,234,235,236,237
658,659,660,661,662,663,664, 1090,1091,1092,1093,1094,1095,1096
etc
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LINKS
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EXAMPLE
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At n=4, the consecutive numbers 68, 69, 70, and 71 have the same prime signature as 76, 77, 78, and 79. Both have the form p^2*q, p*q, p*q*r, and p, respectively.
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CROSSREFS
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Cf. A046523 (smallest number with same prime signature as n).
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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