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Search: id:A124249
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| A124249 |
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Numbers n such that n!!-2^n is prime. |
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+0
2
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| 9, 13, 21, 25, 27, 35, 41, 53, 63, 81, 123, 333, 381, 413, 1187, 2265, 3153, 4211, 4887, 7359
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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All terms are odd.
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EXAMPLE
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9 is in the sequence because 9!!-2^9=433 is prime.
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CROSSREFS
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Cf. A124248.
Sequence in context: A090415 A026283 A026045 this_sequence A137168 A033870 A151901
Adjacent sequences: A124246 A124247 A124248 this_sequence A124250 A124251 A124252
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KEYWORD
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more,nonn
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AUTHOR
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Farideh Firoozbakht (mymontain(AT)yahoo.com), Nov 27 2006
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EXTENSIONS
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Three more terms from Ryan Propper (rpropper(AT)cs.stanford.edu), Nov 05 2007
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