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A137390
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Numbers k for which (9 + k!)/9 is prime.
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50
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8, 46, 87, 168, 259, 262, 292, 329, 446, 1056, 3562, 11819, 26737
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OFFSET
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1,1
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COMMENTS
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No other k exists, for k <= 6000. - Dimitris Zygiridis (dmzyg70(AT)gmail.com), Jul 25 2008
The next number in the sequence, if one exists, is greater than 10944. - Robert Price, Mar 16 2010
Borrowing from A139074 another term in this sequence is 26737. There may be others between 10944 and 26737. - Robert Price, Dec 13 2011
There are no other terms for k < 26738. - Robert Price, Feb 10 2012
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LINKS
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EXAMPLE
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a(11) = 3562 because 3562 is the 11th natural number for which k!/9 + 1 is prime. 3562 is the new term.
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MATHEMATICA
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a = {}; Do[If[PrimeQ[(n! + 9)/9], AppendTo[a, n]], {n, 1, 500}]; a
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PROG
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(PFGW) ABC2 $a!/9+1
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CROSSREFS
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Cf. A139068 (primes of the form (9 + k!)/9).
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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a(11) from Dimitris Zygiridis (dmzyg70(AT)gmail.com), Jul 25 2008
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STATUS
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approved
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