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A145750
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Primes which become emirps when rotated by 180 degrees on a digital clock display.
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1
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661, 1061, 1091, 1181, 1601, 1811, 1901, 6011, 6991, 10061, 10091, 10861, 11681, 16001, 16981, 19001, 19961, 60601, 60611, 69001, 106861, 108161, 108881, 109891, 110881, 116881, 116911, 118081, 118861, 119101, 119611, 160861, 161611, 168601, 169691
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OFFSET
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1,1
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COMMENTS
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The sequence contains all bemirps A048895.
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LINKS
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EXAMPLE
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1109 is a prime. After 2D rotation it is 6011, which is prime. However, 6011 is not an emirp because 1106 is not prime. So 1109 is not in the sequence.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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1109 removed, 6011 inserted etc. by R. J. Mathar, Apr 05 2009
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STATUS
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approved
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