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Search: id:A075409
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| A075409 |
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a(n) is the smallest m such that n!-m and n!+m are both primes. |
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4
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| 0, 1, 5, 7, 19, 19, 31, 17, 11, 17, 83, 67, 353, 227, 163, 59, 61, 113, 353, 31, 1447, 571, 389, 191, 337, 883, 101, 1823, 659, 709, 163, 1361, 439, 307, 1093, 1733, 2491, 1063, 1091, 1999, 1439, 109, 2753, 607, 2617, 269, 103, 2663, 337, 14447, 2221, 5471, 2887
(list; graph; listen)
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OFFSET
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2,3
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COMMENT
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For n=3,5,10,21,171,190,348, n! is an interprime, the average of two consecutive primes, see A053709. In general n! may be average of several pairs of primes, in which case the minimal distance is in the sequence. See also n^n and n!! as average of two primes in A075468 and A075410.
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EXAMPLE
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a(4)=5 because 4!=24 and 19 and 25 are primes with smallest distance 5 from 4!.
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CROSSREFS
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Cf. A053709, A075468, A075410.
Sequence in context: A116623 A046151 A046078 this_sequence A058079 A076787 A094963
Adjacent sequences: A075406 A075407 A075408 this_sequence A075410 A075411 A075412
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), Sep 18 2002
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EXTENSIONS
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More terms from David Wasserman (dwasserm(AT)earthlink.net), Jan 17 2005
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